I had a 1973 Ford 3000 gas for 30 years. It had a loader also. Mine was shot by the time I decided it needed to re-locate.
They are VERY popular tractors. Even tha gasser is a good seller. They use a fair amount of gas per hr for the size, but aren't excessively bad. They tend to be cold natured especially as it gets older. Mine ( and a few others I know of) had an unnatural appetite for ignition coils. (averaged 1 every couple years)
Mine was used primarily as a "barnyard tractor" with a manure loader on it from new. The reason why I decided to sell it was the entire front end was trashed. Axle was sagging, bolster was worn, steering linkage was shot, spindles were bent, ect.... Too long with too much loader on too light of a tractor for the work I gave it. I sold it, bought a '72 3000 diesel, swapped the loader, and ended up selling that tractor too. I got $3850 out of the gas 3000 w/o loader, $5750 out of the diesel 3000 w/ loader. (Kelly "aftemarket" loader, but a good one)
Price; Hmmm Towards the high end of the spectrum, but not totally out of the realm of possibility IF it's truely in that great of condition. You'll find 3000's without loaders anywhere from $3000 to $6000 around here. Loader usually adds $1000 to $2000. A really NICE tractor/loader combo can bring more, but no matter HOW NICE, that's still a 35 to 40 year old tractor. It's only worth so much no matter how nice.
I buy with an eye towards resale. With that in mind, I wouldn't give that much. But if your friend wants a tractor to keep, that might not be such a terrible deal. Just go over it with a fine toothed comb. Make SURE it's as mint as described.