I'd just order swatches. It's always a good idea to order swatches or you might be in for an unpleasant surprise. I learned that the hard way when I first started buying fabric on-line - now I only ever order without a swatch if it's a trusted company from whom I've bought before and there's basis for comparison with what I've previously bought.
I really don't like high polyester content, but if you're on a budget I understand. It will, however, make the costume more "stuffy" to wear and hot and it will feel and likely have a shine that's plastic-y (which I don't think is the best for the really organic feel of FFIX).
Disclaimer : This post written by a Grumpy Old Man
Actually in the pipes:
- Remaking Ser Loras doublet.
- Luke Skywalker, A New Hope
- Wind Waker starter costume in swim material
Eventually: Paul from Dune, Faramir, Harry Sullivan