I paid £150 last year for a nuc, and it was so successful that I'm just about to pay £160 for another one which I'm picking up on Saturday from the same guy. I bought from him because highly recommended locally, so would suggest if you can be sure of your supplier this could a reasonable price (although I'm in Surrey, & from what I see prices can vary a good deal around the country probably because of demand, I don't know about demand where you are).
Out of interest, at a local auction last weekend, three full size colonies went for prices ranging from £255 to £345, which is surely more than they could be worth economically, but there's a lot of hobbyists round here anxious to stock up (and presumably with plenty of money!)