if it isn't too far away for you, I'd jump on that one for $250 in DeForest. Any of the units that you are considering are 40-ish years old +. Which is a good thing, they have forgotten since, how to build a good machine. Today's wont be around with parts still available 40 years from now.
I'd expect to have to put a little work into anything I get. For the price, you have the largest cushion for that possibility, as opposed to the others on your list. Sometimes higher price doesn't mean better machine.
I have seen people wanting more for a deck than that, certainly just engines alone, people are wanting more. I have a 1650 roller that I have decided to sell because the only engines I can find are a couple states away and $100 more than that whole tractor, not counting shipping.... lets see.... $350 + ship for an engine or $250 for a runnable complete tractor in good overall shape......
I am not looking for any projects right now, since I have plenty/ but Deforest is just north of Madison, about 300 miles away from me. If I needed a machine, that one looks good enough to seriously consider a road trip....
I've camped at the KOA there/ if I needed a machine I'd probably do it again to go after that one. What are you waiting for?
That red one on rockford CL would have been a good deal at $400 when it was still in St Charles, IL last week... but another 50-60 miles away (for me anyways) and more than 2x the price? no way. I'd bet my last dollar that the current seller did little to nothing to it besides go pick it up, set it into his yard and put it back up for sale.
there was a nice looking 129 in Palatine IL (Chicago CL) last year that lingered on CL for quite a while and I don't know why.... looked like a better deal than this red (not stock color) one... though I know that paint color has nothing to do with how well a machine does a given job.