Pics wont open (my internet really does suck!), how much of the thread was damaged? I'd say provided there is enough left to hold the nut on (and I'm afraid to say it'll be the MOT tester that decides if there's enough I'm afraid) then I'd say you should be ok. If your tester is a sympathetic bloke he might let you off if you explain you had trouble with parts and that the new ones are in transit, gotta be worth a shot?