Thanks, jags!
I surely appreciate your having a look, and also the bother it took! No...I think that's about it for any remaining needed parts.
When I started on the Folder, I used a pair of drop 'bars with the hooks cut off and flipped top-for-bottom.. I then milled out the clamps on some Deore thumb-shifters and slid those on the 'bars, up near the stem. I took a pair of Tektro MTB brake levers, milled out the clamps for them, and re-forged the lever blades so they arc'd around the bend of the 'bars. A lot of work, but it worked nicely and folded compactly with the bike. After all that, I have now decided I would prefer a set of wider bullhorn/road pursuit 'bars with bar-end shifters and a set of Tektro interrupter levers reversed to mount near the ends.
It certainly has been a fun project, and the full suspension works nicely in all my tests. I just want to finish it up this summer, wet-paint it, and get it on the road! Out for a full-blown tour would be even better. No pics, 'cos they wouldn't be appropriate for the Thorn-specific forum, but it is the same in spirit as Danneaux's Sherpa, just folding and with small wheels. As for color...I've decided to Paint It Black (matte, of course); it'll look like Sherpa's baby brother.
Thanks again very kindly for taking a look in your parts bin for me.
All the best,
Dan.