I agree with Arctic. $250 would be about average for a standard T/C Hawken in decent condition. By decent I would expect to see a couple nicks and dings from normal use but nothing major. If it was in excellent to mint condition you could expect to pay up to an additional $100 - $150 more. And then there are the special edition models which carry an even higher price tag.
There is one at my gun shop that is selling for $175. The wood is in good shape but the bore is questionable. I tried looking at it tonight with a bore light and it was very dull looking. Not sure it it was surface corrosion or just dusty/dirty.