No kidding! I looked several years for a YM186D. (Smallest Yanmar with PowerShift). I finally found the one without loader in Susanville, 5 hours / 300 miles NE, and over behind the Sierra Nevada range, driving from N of San Francisco to there via Reno. I paid the seller to bring it down the mountain to Dave's Tractors in Red Bluff. Then two separate day trips, a hundred miles each in low-traffic hours, to get it to my home, then from there to the ranch.
A couple of years later I finally found the ideal one, with power steering and loader. That was in Marin County, only an hour trip.
I've only seen a few others, or anything with PowerShift, on eBay or Craigslist over a 15 year interval.
Each YM186D looks like a prior owner must have had a psycho girlfriend - dents everywhere! And both look like they never spent a night stored indoors, over their 30+ year lives. But both are mechanically sound. That first one dyno-tested more horsepower than spec new. I haven't tested the loader one, but it is just as strong. These aren't pretty like a VN 'rebuilt' but at least their prices reflected their appearance.
I cleaned up and repainted all the wheels and put on new seats. And I just bought the replica top grille for the loader YM186D. I plan to clean that one up - eventually. I sold the non-loader one to a local guy who did a complete appearance restoration and it looks great now.
Like you said - "in my corner of the world, used tractors are like hen's teeth".
Richriddle - There are no regulations on buying used tractors like these but I think at 50 hp is where smog rules apply and some older tractors have to be sold out of state. Something like that. Maybe the rules are only for tractors sold new.