I had a good friend (since deceased) who was very into r-r, and he settled on Otari. But really, this is such an esoteric catagory and decent tapes are so expensive and limited in scope that it’s hard to justify the price of entry. Yes, they sound amazing, but seriously, you’ll spend THOUSANDS to listen to a handful of good recordings.
OTOH, find an old Webcor in decent condition, scour your local thrift shops for commecrial r-r tapes, and you could have some fun. Otherwise, I wouldn't go down this rabbit hole.

