Not many hours on that B7100 for its year,/w3tcompact/icons/shocked.gif and if the price is right and you don't mine a manual transmission & non power steering I would be intrested.
To give you an idea of a second hand B7100 going for in this area,my local dealer has a B7100DT,1978,2.144hrs,16hp,fwd,6speed,fel,very clean and tight,asking $6,595.oo and has a hold tag on it.
If the B7100 as good as you say it is w/a fair price,might be wise to check tad futher in to it.
Just one thing to remember..no power steering and w/a bucket full its hard to turn tight corners,also little rough on the knuckles and fingers if the front tires bump up against something. /w3tcompact/icons/crazy.gif
I was recently shopping for used B7100's in my area (Pennsylvania), and can give you some prices to compare. I found 2 in pretty good condition. Both HST, 4WD 1981 or 1982, with 60" MMM. No FEL.
One was 2200 hours, asking about 5K. The other was only 530 hours, and the dealer was asking $6500, but would let me have it for $6300.
FWIW, I thought that was a tad overpriced, and ended up doing much better by finding someone who was selling a tractor privately, although out of state.