Source of Dacron?

As part of my welding practice, I'm going to build a small control
surface "look-alike" ( I have access to Tcraft blueprints so what I
build will look vaguely like a real part) . I'd like to take the
opportunity to learn a bit about covering, but don't want to spend
money on Ceconite if it's REALLY just Dacron.

Dacron out of a fabric shop is already shrunk.

Can someone suggest a source for unshrunk Dacron?

I guess I could find who makes it and order a few yards, but if
someone has already gone down this path.... - Mike