I modeled out a 3D-Printable insert for the Anbernic RG35XXSP based on the dimensions circulated online. A combination of Multi-Material Printing and patterned build plate allowed me to produce a pretty nice design to put in my handheld. So, I figure it is worth sharing the base model I used to make it in case anybody else wants to give it a try.

You will want to print this with two layers, so try to get your layer height down to 0.1mm or lower. Also, turning down your print speed is recommended. The model is face-up, so flip it upside-down if you want to use your bed texture as part of the design.