From what I can see the only option for an open back tenor case is the TKL 7838? I kind of need a new case but that seems to be the only option? Any others? Seems almost impossible to find even one of those.
Saga Music appears to list two new cases, Superior CD-153CT, and Superior CD-1355T, for openback tenors. I think the first has a 12 1/4” opening and the second is for 11” tenors. I Googled Superior banjo cases, and got the Saga website, where I found them. If I’m right, and that’s always a big “if,” it appears, too, that Amazon has a great deal on the larger case. I stumbled upon it, there, for less than $55.00. (Worth a check, though I could easily have misread something.)