The case ... dunno, but since you live in the UK, you could get the cheap QTEC 550 W PSU and it would wirk fine. I have it and it's CHEAP and rockstable..with 2 fans. I lived in London so I am not sure they have it elsewhere.
look on www.ebuyer.co.uk or www.aria.co.uk this is where i get all my computer stuff from. becareful though, and sign for it unchecked, shouldnt be a problem for psu but if you order other stuff like cases, then they can be damaged in transit, which is a bugger and they charge you to return it, which is stupid. anyway ebuyer's cheaper but aria is more reliable. hope this helps