Hi Mikael,
I put Pirelli P5's 215/70VR15 on mine in around 1989 and they are still on there. Have been garaged all that time, and only done around 10,000km. I inspect them very closely for any sign of perishing/cracking and they are still good, but still I will be faced with a similar question soon.
At the time there was little choice in VR rated tyres - only Michelin which was 50% more expensive than the Pirellis. I think the originals were English made Avon Turbospeed 70's, which I was told used to be fitted to Rolls Royces etc.
I still have one of the original 36 year old Avons on a spare but very corroded Campy rim. (not usable)
The owner's handbook just says to use 215/70VR15.
best of luck choosing,
Peter
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