How big?
Trimar do them for £22 but I don't know the size and I'm sure I've seen tiny ones in Wharf for around £20.
For £35 I'd expect a fair sized fish, 3"+ at least.
Wholesale Tropicals also ask £35 - but their's are more like 4". That said I think it's a bargain. I paid £30 for a 2" one once.
£28 in Oasis, Manchester for a 3-4 inch specimin, nice fish too.
Paid £30 for my 3" one from work (before discount), so £35 sounds like a pretty fair price.
Ben