I'd suggest searching ebay for one with a similar keyboard (processor etc. need not be the same) and then go to the repair guy (not PC World, but the guy in the corner shop in the cheap part of town) and ask him to make one good out of the two.
I've seen loads on ebay with dud screens (the expensive bit) go for £30.00 or so.
Try a seach "sony vaio spares" to start with.