The prices are in line with what we have here in the US. I know a little about the Pound vs. US dollar. We need to see your spec's and the PSU brand and model plus how many watts it is.
I know over here by law they have to disclose if it is refurbished or not and/or used. But that is here. The difference in the two cards you linked us to is, one has 2gb of Vram and the other with 1 gb of Vram.
To get the full benefit of the 2 gb of Vram is to have more than one monitor and your resolution is over 1920 x 1200. Unless you are doing that I would stick to the 1 gb do to the price.