Hello, I’m going to move this thread to the appropriate place, since Free Laser Designs is for posting your patterns to share with others. If you use the search function, there have been many discussions about where to find acrylic.
Here is just a result from a quick search:
That being said, I’ve purchased from jpplus.com and https://www.engraving-supplies.com/. But there are a lot of other suppliers and I’ve seen people recommend Inventibles, local shops, and Etsy. Just make sure you look for cast acrylic. I like the going with the ones that make supplies specifically for lasers so I don’t have to worry too much about it being safe to cut or not.