To be honest I don't think il have time to remove head, and either wait for current head to be repaired or wait for new head. I think my best option is to refit a cheap chain and tensioner, time it up, hand crank it, compression test it, hope that only one or two valves have bent and that the engine will run even if in limp mode so I can drive it somewhere to have the head removed and repaired. I did as r5gtt suggested and bought the future in laws some wine to try and butter them up but I think I've still only got one week, two max and it'll take longer than that to sort out the head. It's a shame because strangely enough I'm enjoying the various bits of work I'm doing and would like the chance to take the head off to better understand the engine. Plus it would be serious DIY points in my books