I would though image price gets too high if those are sold as pre-assembled. (These devices are hand made, and not manufactured by a real manufacturing line that manufactures thousands per day) Are you able to solder? I think most of the guys developing HW here are willing to sell off their PCB, so you "only" have to solder connectors and a few lead through components to the PCB to assemble the PCB together.
If you are not able to handle soldering, then search for the nearest Fablab in your area, as there are skilled people that most likely are willing to teach you how to solder: https://www.fablabs.io/
This could be a good start:
More good stuff to be found via this link: