Not many documents received, eh Flikitos? Perhaps I could assist. If you still need any help, mind telling any specifics which you still need?
I could give a start. Here is a few models for zamburak guns. I noticed the zamburak units in this game (camel gunners, elephant gunners, etc.) still use the normal jezail skin. It's rather funny to see them fire their cannonballs from them.
I believe this is an ottoman abus gun model, but it's probably similar enough. Though I think both they and zamburak guns had tripods/howdahs (to mount on camels/elephants), which I'm guessing is graphically inconvenient.
Oh, but here's more realistic ones! It's just that they look hard to create...
CAMEL GUNNERS
I also have some skins possible for North Indian soldiers early on. It is quite difficult to find historical images. But, seeing as many melee troops in the 18th Century were clad in medieval armour (this set of armour shown actually is 18th Century), I took some pics of units in MTW's Broken Crescent mod. Considering that Ahiga made these (so convenient!), perhaps he has considered reusing some of them for Empire? They are very well done!
RTW Broken Crescent Models for Early North Indian Troops