If it currently runs, first thing I would check is the length of the band adjustment screw threads. If the screw is all the way in, or just about to the lock nut, the bands are worn out and I would reject it.
Second, all the SOS mechanics around here died off and there is no one to fix it even if parts are available.
I had one that was well worn and I had to lift the cover and fix something, PTO cable I think. I had adjusted the bands their last time but they lasted for me.
I gave $1000 for mine in a Ford 4000 4 cyl diesel non-running with the Ford loader. Had I known what I know now I wouldn't have given that, or would have just passed it over.
My opinion. Not good news but my encounter.