I have this old cherner-style (but unmarked) bent ply chair that we bought in terrible condition 20 years ago and used as a side chair until one of the legs snapped. We had it repaired (glued) and then it broke again a few years later beyond repair.

I want to put the seat on legs, but searching high and low, I have no idea where to even start.

An Eames H-base (DSX) narrow-mount would still be too wide as the screw holes are 5" apart on center side-to-side and 5 1/1" front-to-back.