There are a couple of options. Both Starboard and Lexan are easy to work with standard wood working tools. Also, someone may make one that will fit your cutout or the cutout can be enlarged. I would start with Blue Sea and Marinco.
2015 Seaark 1872 MV CC Etec-90
Helix 12 CHIRP SI, HB 1199, MinnKota Riptide ST80/i-pilot Link, Bob's Hydraulic
Bitter Gun Owner