£2.5 to £3 sounds high to me. I was looking at a 51 reg with similar miles quite a while back and it was in a garage for £3k and in black which I think would be a better seller than Green.
I'd guess at somewhere nearer £2k private but you may get more if someone's really after a Puma, it's a good'un and you can verify the mileage with MOT's and a good service history