Ever think about making your own? I haven't done it yet but I'm going to give it a try myself. Check these sites out.

http://www.customsawing.com/index.html
http://www.customcalls.com/index.html
http://brooksidegamecalls.com/

You can get lots of info about call making at the NWTF website, there are a bunch of call makers on there that'll answer any questions you have.

http://www.nwtf.org/