Hi Swamper8, welcome to the forums.
I've seen people making these (custom gauge overlays), so if you just want them for personal use the best solution would be to buy from someone with the equipment that already does it. If you're looking to sell them, read on.
The material in your picture appears to be an ABS, or thermoplastic. These can be etched and cut with a laser but since the material melts rather than vapourizes it is difficult to get 'clean' results. You could also use a CNC router and reverse engrave, then fill with clear resin.
It may be easier to create a sandwich using 2 or 3 thin layers, a laser would be a good choice. It could do the fine engraving of the top layer and cut the transparent layer and then the final back (if needed).
Your budget will limit options, but it is possible to build a small CNC router for that and you can also buy a used or Chinese small desktop laser for about that - so I think you can make it work.
Another option that may work is 3D printing, I don't have any experience with this technique but it would be worth looking into. Not sure about the cost.