[tonythetarga]

It is hard to say since we don't know how it was driven for those miles. I think that with the fewer miles it should be OK as long as oil changes were done about once a year regardless of the low miles per year. If you buy it, consider the direct oil feed system for the non-serviceable bearing. It involves a new door to the IMS with an oil line and spray feature to the ball bearings. You do have to remove the outer seal of the bearing so oil gets in there. I'd negotiate in the 2k you'll need for parts and service (provided it doesn't need a clutch too). In any event, put in a new throw out bearing while you're there as they are plastic, inexpensive and do wear out before the clutch does.
Look at it this way, if the car only had 12,000 miles from new would you consider buying it? Probably yes, hell yes!
These bearings aren't that delicate, so with only 12k on it, it should be good as long as it hasn't sat in dirty oil with contaminants built up in it. 12K miles and no oil change for 6 years isn't good but if the changes were done frequently, then I wouldn't worry about it.