Denny,
If you have a drawing it won't hurt to send it to the bellofram guys to see what a custom mold will cost. You may be surprised at how cheap it is for a small diaphragm. If you need round material they may also sell you round or sheet directly. Did you look through the catalog to see if they had something close or a match?
My company does a lot of business with them so I can also try to call them and get some free/cheap samples of raw material. Let me know.
Last edited by RingLeader; 02/25/2012 5:39 PM.