I just got one off of eBay. It was an 18" fuge and it was acrylic. Was 25 bucks..came in pieces and it took about an hour to put together. They even had great instructions and acrylic glue in the kit. It works awesome!!
It was sold by USA Aquariums ..just search for regugium and then look at their eBay store..they have all different sizes.
So far, no leaks, and it works like a charm..just put some mud, chaeto and rubble in it, and already, there are lots of pods
for my Mandarin (thats why I got it)