You've really beat me to it with this one. I've actually just had some sheets of acrylic laser cut from a company on eBay. It's cost me around £45 so far but it's perfectly cut in 5mm and 2mm acrylic. I've got a floor piece, backdrop with panel detailing and side panels cut. Just need to glue things up and then spray with primer to start things moving. There are very small Lego plates as gold ingots but you can
get them in grey and they're used for detailing on ships etc. I'll be adding a couple of those onto the extruded panels for detailing. Should work really nicely. They cost around 10p each too. I'll just use some filler to cover the bottom groove with the Lego logo stamp.
I think if I was just getting back panels cut it'd be around £20 in total. They're measured to fit into a Kallax IKEA bookshelf aperture perfectly.
I'll set up a new thread rather than clutter or hijack yours with them. Your progress looks really good though. I just couldn't face cutting those curved light sections by hand.