There is an organization for which there is a web site:

https://limbitless-solutions.org/

I was lucky enough to attend a presentation at our local library by this group. The web site indicates that the efforts are for children, but I suspect that they may be able to assist you, even if it is only to point you in the right direction for additional resources.

If you find aspects of the project you are undertaking to be problematic, be sure to post your questions here, as I follow this forum and enjoy assisting when I can. I frequently wish I had more design skills, in order to develop models of this nature. My skill set is but a drop in the ocean of 3D printing design.