johnny like all businesses there's good and bad and it doesn't sound to me like they're trying to rip you off even at £200. An MOT is at least 30 quid, a spring will be 50 and 4 hours labour for spring, pads and test at least another £120.
You'll get it back tomorrow with the work done and an MOT so all sounds quite reasonable to me mate
Its funny but we don't mind paying £3 for a pint of flavoured water yet someone shouldn't make any money on parts