The Buzz Kidder sporrans sold by many kilt stores linked through this site are in the $55-60 range and are just about the best ones for funtionality out there.

They are:
http://giftshop.scottishtartans.org/sporran.html
http://www.usakilts.com/sporrans.php

and other sellers (if you feel the need, PM me and I'll add ya to the list)

For the price, quality, looks, and usablilty, they are HARD to beat (I now have 2 of them)