Hello John: I have given your inquiry some thought and would like to offer several options for you to chew on.
1. Is the master pin out of the chain or is the chain broken at some other or at several locations rather than at the master pin?
Do you have access to a metal supplier. I would take a micrometer and measure the Pin OD then proceed to a metal shop and cut one to length and do a temporary install.
2. If that option does not fix the broken track problem, can you fix an oak beam to the bottom of the rail and grease the heck out of it and winch it forward enough on some sheet metal or on to a sheet of High Density Polyethylene to get it on to an equipment trailer. Landfills use the HDPE for thier liners and it has a low coefficient of friction. If you go to the landfill you could probably get a sheet for cheap. The oak or hardwood beam would be affixed in such a way so the idler and the sprocket do not touch the ground.
3. Years ago, the Frank G. Hough Corporation supplied a two wheeled donkey that would affix to the rails of some Allis Crawlers that so that the whole machine could lifted off the ground and could be transported. I am uncertain if these Hough donkeys could be used on other brands, such as Cletrac's.
4. Do you have access to a welder?? Can you do some field fabricating at least enough to stitch the track together, then move the machine that way???
Well not sure any of these will work, but some thoughts that might lead to a solution. Hope you get the machine. Wish I was there to lend a hand. Take Care John... Orangeman.
Thanks for some good suggestions! I spoke with the seller - he has a welder and will do a quick repair to the chain and get it back on the tractor. Most of the transporters I contacted would only take the job if it moved on its own.