You can contact Martin Accordions in Scott, La. Talk to fellow forumite Clarence “Junior” Martin or his daughter Penny. I provided him with the original prototype I had and he’s professionally built 2 that I know of. I have one and the other is his. The design is perfect for right-hand practice, but is also useful for left hand practice. Another thing, you can use it to practice tuning by ear. It will fit in a backpack so you can bring it wherever you want and practice at your convenience. If I can find some pics of mine I’ll post them. Below is a pic of the prototype that I used for 15+ years while touring and working full-time.
Please bear in mind that I’m not building these and all inquiries need to be with The Martin Accordion folks.
