Firstly, welcome to the forum.
As for the chinese copies on ebay, personally I would steer clear if you're in any doubt as to whether it is good value or not. I guess posting here shows you've got your doubts.
A quick google products search has shown up one from a more trustworthy looking source (IMO)
here for just under £25 delivered. I say more trustworthy looking because they have their phone number displayed at the top of every page. It still appears to be a Canon compatible part rather than the genuine item though.
If you decide to go for a genuine one rather than a copy, then
7dayshop have it for £39.99, although they can sometimes be slow with delivery.
HTH.