If it helps at all, they're very simple to make your own. I buy the right sized circular piece of Teflon, get some industrial strength Velcro from Lowe's or Home Depot, sand the back of the disc lightly to stick better, cut a piece of Velcro larger than the disc, stick the 2 together and trim the excess. Takes maybe 1 minute or less to make each one.
I get my discs from this Ebay seller:
http://www.ebay.com/sch/rubbermann7/m.html?ssPageName=STRK%3AMEFSXS%3AMESOI&_trksid=p2053788.m1543.l2654The size needed is 1 7/32", but 1 3/16" does as well. They're 1/16" (.062") thick. If he doesn't have them listed, I just email him and ask what he wants for a minimum purchase (can be 100 - 500). FYI They come in different colors; sometimes I got white, sometimes blue. All of one order will be the same color.
If you like, send me your name and address via a private message and I'll send you a few I made as well as a few plain Teflon discs.
EDIT: I see MI_2_AZ posted similar; we have shared this info and sent each other sample of what we each had obtained.