You've got a number of options, here's the order I would approach them in:
Motortune Shotts - big peter knows what he's tinkering with...cost probably < £100
CLCM in sighthill, Edinburgh - a bit away but this guy is a specialist and used to do geometry for Edin OPC before they got their own kit, also < £100
Kenneth Brown, Hillington - gets mixed reviews, I didn't have a great experience (attitude rather than workmanship) but others swear by him...no clue on cost
George Morrison, Rutherglen - not 100% sure he can do geometry, but sure he'd charge you a fortune and get it done somehow...workmanship good, pot luck pricing (take the KY)
Edinburgh OPC - if you've gotta go to the dealer, they're probably the best in the UK...about £250
Glasgow OPC - the opposite of the above....£250