Thanks for the pointers to those companies guys (and the offer to rummage through your garage Ian). BTW, I found the address for Specialised Plastics:
http://www.specialisedwholesale.com.au/site/index.cfm
I'll probably go with the real deal and order a couple of small sheets of teflon from one of them.
I'd still be interested to hear people's view on the UHMWPE though.
Cheers,
Chris