Yamaha TT500

I have been told where there is a TT 500 for sale locally, I haven't seen it yet but have been told its an American import and the guy wants about £1 K for it!
Whats the difference between this and a XT 500 ?
Are they anything special and any comments re value ?

All advice etc welcome .

Bomber

Not a lot ...

... of difference, or so it would appear. The TT had a much larger collector/silencer, but that'll have rotted away by now; but a Grand for a '70's kickstart Yamaha seems a lot This thread on Advrider seems to think the TT was an off-road variant of the XT.