If only there was a way to cut plexiglass without a laser… I’ve used jigsaws, scrollsaws, routers, hand-saws e.g. jeweler’s/fret saw. You will need a bit more plexi to play with and a bit more time, but the results should be just as good.
There are probably numerous off the shelf items that could be re-purposed as a housing. The first thing that popped into my head was a little bamboo steamer box, since it should be relatively easy to remove the woven stuff and replace with plexi:
