Builder in either Phoenix, AZ or Boston, MA?

I wonder anybody knows someone who can build a speciality item for me, in either Phoenix, AZ or Boston, MA.

I’m trying to put together a somewhat specialty item (as if electric boards aren’t special enough). My 96-year old Dad came across a video of a motorized walker ( at around 1:34) - and started jonesing for one. I figure I’ll build him one - starting with the parts used for electric skateboards - this is really about attaching a powered platform to a walker frame - not that different from an electric board, except that it will be a LOT slower.

I can probably build it myself, but I’d just as soon find someone who could build it for me - who already knows what’s available in the way of parts, and has all the necessary tools at hand. My Dad’s in Phoenix, I’m in Boston - so if there’s someone out there, or you know somebody - a pointer would be very much appreciated.