Well if I can get more of the studs out successfully it should drop the quote - he was quoting for removing 7 studs to be fair 
Update: I've been out in the garden hammering away with my impact driver and successfully removed 5 of the offending studs. 1 more however decided to snap off flush with the head but at least there are only 2 studs to deal with, instead of 7
Going to give one more machine shop a quick ring and see what they say
Update 2: Right, I've dropped off the engine with this other company who seemed much more helpful and said that it should be around £25 which is much more acceptable
Mind you, my thumb is certainly hurting after hitting with the hammer several times :wall

Update: I've been out in the garden hammering away with my impact driver and successfully removed 5 of the offending studs. 1 more however decided to snap off flush with the head but at least there are only 2 studs to deal with, instead of 7

Going to give one more machine shop a quick ring and see what they say

Update 2: Right, I've dropped off the engine with this other company who seemed much more helpful and said that it should be around £25 which is much more acceptable
