Two coils arrived in the post today, got them from these guys:

http://www.usautomotive.co.uk/

The lady on the phone new exactly what I was talking about even when I mentioned the MG and they came extremely quick so a big thumbs up from me!

The local MG garage took a while to cotton on initially offering me a single coil pack for £140 (when I say 1, in that they thought the car only had one) and then on investigating deciding that they couldnt supply this part at all, have they no imagination!?

Anyhoo, went back the car tool kit in hand and swapped over the number 4 coil, which incidently is probably one of the easiest to do, only had to unscrew the fuel rail mount to get a little more room, but no need to remove anything.

Got it in and car fired up, was a bit wobbly but then was fine, engine light went out too and it is running fine again.

Got a spare now too!

Tested the other 7 and they are all okay.

Thanks for all the replies on here.