New head bolts or not?

[arcon]

Ok, doing head gasket on a 1996 rover 214. New gasket ordered and head being skimmed. I know they are stretch bolts, but can I get away with using the old ones? It's a very old car, i'm only fixing as I took it in p/x as an MOT failure and it turned out to be more than a failed MOT... so I want to repair it cheap cheap cheap...

Will it really be catastrophic to not order new bolts?