Thanks! As for the antron (or nylon fleece), it’s not a particularly easy material to find outside of specialized puppet making supply vendors. I’ve always purchased them online as well. The two main vendors that I’ve purchased from is Puppet Pelts in the USA, and Weird Kid Store in Canada. I actually really like the Weird Kid Store version, as it’s much more textured and has a slightly more vintage look to it—a personal preference of mine. Unfortunately, even ordering from and shipping within the USA, it can get expensive! Typically the most expensive part of any puppet build.
Some people have used standard polar fleece, which doesn’t have that subtle ’sparkly’ look that the nylon fleece has, but it can work for a Kermit build, or other puppets as well. It also tends to be easier to find at craft stores, depending on where you are. I’m not familiar with Dacron or Tergal stretch, if they’re not too expensive, It may be worth trying out just to see how it looks. I think in the beginning, if you’re looking to experiment with materials, it’s great to try a few different options. I do think though, after you feel comfortable jumping into a finalized build, that investing in the nylon/antron fleece would be worth it! It’s just really hard to find anything comparable to it.