I make scratch plates for my Tele mule from thin polystyrene sheet off of eBay. In the style of early Fender plates made from Garolite, with no bevel, just softly rounded so as not to catch my delicate little paws.
It is very easy shape with Stanley blades and fine abrasive papers. The only problem is its flexibility, which means screw holes have to be big enough to avoid imposing flex forces. Plus it picks up a lot of gunk from fingers.
Ease of working is important for me in the absence of workspace and tools.