I've been reading your progress on your rebuild project. By coincidence, I came across a flea market buy of a Steven 235.
It was crusted with rust, buttstock gone, and, like your's, left hammer missing.
The action is otherwise complete and barrels match and is tight. The forend is a missmatch. Maybe off a 311 or some other Stevens. It had a good and correct buttplate.
I visited a retired gunsmith that went through a pocket full of Stevens hammers. All right hand! He had one left hand hammer that would work but didn't match. I suspect it's off of a 215 or 225.
I'm looking for an original 235 buttstock in usable condition just to complete the gun. But this winter I may drag it out and make a buttstock and forend.
Keep up the good work.