I have an almost complete collection of £2 coins and i have seen loads of those types of coins on a large auction site and i don't know why but sometimes they sell well and others not at all.
A lot of people think that part of missing words, offset stamping and upside down edge writing makes their coin worth a lot but i don't think that is always the case and also it seems that most 50p's and £2 coins just lately are being offered as rare.
For reference and information I like this site http://ukfakeanderrorcoins.50webs.com/index.htm
You could put it on a large auction site and try and you may be lucky but at the end of the day it is worth £2
I have seen £2 coins sell for .99p and £1.20 P&P and obviously they are out of pocket on sales like that.
Now if you had a Northern Ireland commonwealth games £2 coin that would be a different story.
Dave