Ouch!

I think that this is a swappable part. Please see attached.

Hi John
Thank you for the kind offer...i have been doing copious amounts of research and had come to the same conclusion and i have found one for sale from the same people i got the replacement alternator from so i can have it here for tuesday so it looks like im going to have to bite the bullet and replace the lower chain cover.Interestingly whilst researching ive seen at least 4 pictures in various forums of the exact same damage at the exact same bolt hole..so its definitely a weak point and as the bolts only need 10 nm its a quite easy to overtorque (the bolts i was used to tightening when i was at work required upwards of 5000nm...10nm does not compute) it also explains the unexplained coolant losses over a long period of time ...so time to dust off my spanners and get reading 3 coats of looking at it and 2 coats of thinking about it should be a good start
Once again thanks for the offer

You're half way in to doing the timing chains by having to replace that cover.

Unfortunately due to circumstances that will have to wait...the imperative at the moment is get it running which with a good wind and a dose of british good luck will be tomorrow...just got to prise the old cover out today and wait for the parts to arrive to finish...the hardest part of the job was a rounded allen bolt in the oil cooler took me best part of 3 hours to shift it yesterday

With hindsight i should have just stuck the dislodged piece back in with some chemical metal paste and took it to the scrapyard !