I dont really understand what you are after. I wouldnt say that I am an expert, but I do make some sporrans myself. Are you looking to make a drawstring "rob roy"-ish sporran, or something out of stiffer leather? In either case a whole hide is going to be enough to turn out A LOT of sporrans. Its kind of overkill unless you plan on selling off a bunch. I figure when I make a rob roy I put about 3 sq ft into each one, and that is of a garment weight leather. If you want to do tooling, (which I have yet to do on a sporran), veg tan is the only way to go. Wet it down a little and stamp/carve away. I would use a leather between 6-8 oz for that.

BB