Here's a simple trick I tried for making an instrument panel. The plastic sheet is 0.75mm white "plasticard" (HIPS), widely used in modelmaking. I raster-engraved the markings using the laser to a shallow depth (maybe 0.25mm), then sanded the surface down by hand to remove some of the melted lumps formed near the engraving. Next, I painted the engraved areas with black Humbrol enamel paint. Once dried (on a hotplate), I then scraped & sanded off the paint to reveal the markings. The results are quite effective.
Note that you do get proper laser-engraving laminate, which comes in a wide range of colours, but it's thicker (1.6mm) and only available in full-sized sheets (over 1000 x 600mm!).
This isn't intended as a free-standing panel, since it's obviously very floppy. It will be held in place on the outside of the instrument case by the various controls - potentiometers, switches etc.