While acrylic does scratch it can be buffed out unlike glass when once it scratches it stays scratched. Just be sure never to use a razor on the acrylic and you will be fine. I have a 150 gallon acrylic saltwater tank and I just use an old credit card to clean the sides and have never had an issue.

Hope this helps. As for the price I would just custom build one yourself. I built a 4x2x2 for less than 150 with sliding glass front, removable top, out of melamine. Seeing as garters don't require high humidity you don't even have to treat the wood with a polyurethane based primer. I used 3/4 inch melamine with all my cages/racks and never had a problem.