Nice. Been playing with this idea for decades - I patented the LapLift in 1993, and got scooped anyway. Made a few bucks for a while. Then resurrected the idea in 2012 with the attached folding version. Originally it was designed to provide a wrist rest when portables had keyboards right at the front, then the whole idea was obsoleted by portable makers' case design change, with a wrist rest in the front. Even so, having an even larger palm rest is more comfortable. I pitched the idea on Quirky, got no traction.
You know about all the 3D model selling sites there are now? I sold a 3D model on cgtrader. Search on this - there's now dozens of selling sites, where you can post your model library and make a few bucks with no more work. Even better if your objects are 3D printable. Good luck.