Seems like there are often cheap PTO winches on Craigslist here, but they are from trucks. The problem would be making it reverse using a tractor PTO.
Bruce
Hey guys,
Many moons ago I used a old truck type PTO winch to make a portable logging type winch. I used an 10 horse, horizontal shaft lawn tractor engine for power. To get reverse out of the thing, I salvaged a reversing gear box off of a snow-mobile. No speed reduction in it, just F and R. My 'clutch' was just a belt tensioner on a lever, much like a mower deck would use. The winch was a worm drive, so built in load holding.... although all it did was drag stuff.
NV