If there's a Heine Gericke near you try their own brand fully synth 2T 'racing ol'. You can buy it by the litre, but if you buy the 5 litre cans at 30 quid that makes it 6 quid a litre for fully synth. Not bad at all . It looks and smells a lot like Motul 710 to me - which of course is nearer to 12 quid a litre...

I've used it plenty and would certainly recommend it in any case.

Cheers

Wb