Here's a partial update. I found a local rv shop that let me look in some boxes and found that a Valterra trailer deadbolt has the same stud locations and same size actuator. I was able to reuse the deadbolt mechanism as is with the lock cylinder from the new lock. Still trying to salvage the door knob. That's going to be another mess but at least it's secure now.
They have another in stock and I'm going to pick it up and convert the 63 thumb latch travel lock to a deadbolt I think.