Dear Terror A. Part,
who did you request the quotes from? For glass, go to the next hardware store and buy a sheet of ordinary window glass, for polypropylene and teflon, there are plenty of suppliers of virgin teflon and polypropylene (in the US, the first one that comes out of Google is
), for SS coupons contact the suppliers of your equipment to get sheets with the same polishing grade, although the recovery study will show you that the recovery is essentially independant from the polishing grade. Normally you will get them for free as a customer service from the supplier. The only coupons that are somewhat complicated to get are coupons from materials that are proprietary to the manufacturer (e.g. the sinterized filter cartridges from fluid bed dryers) or from glassed equipment, but even in that case suppliers of glassed equipment only charge a reasonable price for them. The point is that if you ask for a quote for cleaning validation coupons for the pharmaceutical industry, the price rises instantaneously at least ten times. Once you got the coupons, clean them with a good degreaser, then with the cleaning agent you use to clean your equipment, and take a blank swab before spiking them for recovery, to get a background and see potential interferences.