I'll have to go take a look in Oakeshotte's "Archaeology of Weaponry" to find out for you. From the top of my head you are looking at a 'leaf' shaped blade in either case at this date and place, and 12' would probably be about right - though maybe a bit long for a lance. Fortunatly for you at this date there really isn't a heck of a lot differentiating the two.

There are probably a couple of people better qualified here to answer the question if you wait a bit. The Italian arms and armour books I have are unfortunately oriented a bit later in date, and of course are written in Italian, of which I don't speak a lick except for being able to say 'Ciao', 'Grazzi', & etc.... I wonder what might be in the Arsenal at Venice? Don't they have a museum there? Help somebody!

I can't seem to find the Leaf-Shaped spear on their website, but it's dimensions are
13.5" Overall 7.5" Blade
it also has a central ridge running down the length

The other is the Long Spear http://store.museumreplicas.com/cgi-bin/www11650.storefront/3aa4 1432006d4e642755d8f5a5060678/Product/View/1681
14.5 Overall 9" Blade

I hope you say the Long Spear, since it'll save me a few bucks

"not particularly good though"
What part of them isn't particularly good?

I just went looking for pictures, and I went to the closest reference I have (next to the computer) A&AoMK. Starting 100 years before - the sivler shrine of Charlemagne at Aachen (pg54)(1207) shows a preponderance of diamond shaped spearheads, with one lone leaf shaped blade.

pg 58, an illustration of the "lives of the two Offas" by Matthew Paris - English, 1250 shows three lance heads - two diamond, one leaf shaped.

pgs 60-61 leaves from the Maciejowsky bible (illus 1280's?) show all diamond shaped heads. Sir John D'Aubernon's brass on pg 64 - roughly of the same date shows a diamond shaped head.

Pg 67 - Sir Geoffrey Lutterals 'portrait' from the Lutteral Psalter (1340) seems to show a leaf shaped head

Pg 74, a detail from the Romance of Alaxander (1338-44) shows a mix of two diamond shaped heads with a leaf shaped head.

150 years too late for Saverio, The rout of San Romano (I've looked at it in My Rennaisance painting book as well) shows a preponderance of leaf shaped heads, a Flemish St. George painted 10 years earlier shows a diamond shaped head. From the 1450's, the tapestry of Hercules initiating the Olympics shows a healthy mix of lance head types.

As I flipped through the book, and looked at illustrations spanning 350 years, for the most part, the head types seemed mixed - now one style predominating, now another, but except in relatively few illustrations, they are mixed together rather than beiong entirely one or the other.

For what its worth....

In Italian warfare,the pavisers provide refuge for the crossbowmen to work from. The assegi is very much shorter and is intended to be used like a gladius. The spears the Italian civic militia carried are to ward off cavalry as well as engage in close combat. An assegi would be as useful as a pixie stick in close order to repel cavalry. You vever know how bloody short 7'-8' is until you kneel or lean over in a front rank to "prepare to recieve". 12' is uncomfortably short (I think thats the pike length used in Red Co due to portage problems). God help me, I'd want mine 16' and not an inch shorter.

I really don't see that much of a problem with a Museum Replicas spearhead - I have seen much worse. You can get a finer copy - if you want to stand in a long line and then pay a fair market wage for the job. This is an item I wouldn't have a problem with coming from that source.

But the classic Zulu technique is the shield smash and the underhand disembowling thrust (Pieter can tell you all about it when he gets back - spent years in the Zulu homeland, Uncle owns a spread there and his first language was Zulu - forgotten now unfortunately. The Assegi can be weilded in an overhand or undrhand grip with equal ease. That is an overhanded hoplite stab.

Since "average" Medieval man was 5'4"-6" tall, then by your reckoning those spears would be shorter still. Thing to keep in mind being the primary flaw of the Medieval artist is lack of perspective, and items like spears are compressed to fit the scene. That short a spear length doesn't fit with the known tactics of the Italian civic militia, and conversely, if a Hoplite can weild a 12' spear in an overhand thrust there is no reason why an Italian militiaman can't as well.

A good place to start study of Medieval tactics is Phillipe Contamines general study on Medieval Warfare. Avoid at all costs the West Point series on Ancient and Medieval Warfare - the work needs major revision to say the least.