Hi, in the very early days of the MK1, spec 503.01 which was 0w-30 was the recommended oil until superseded by 504/507 5w-30 so would probably be fine while the weather is so cold.
Hoggy.

 

I go fully synthetic 5w30 Mannol. Personally would like to use slightly heavier grade, 5w40 synthetic if available , esp on an older engine

 

Napa is a big auto parts chain in US--serving both regular consumers (i.e. retail stores) as well as mechanics and professionals (i.e. providing parts to shops as well as for industrial use). They have a good degree of presence in Canada as well. It sounds like in UK they may be more on the second side of the spectrum as if you've never heard of them they probably don't have many or any consumer retail stores.

Napa does not make oil (nor many of the parts they sell under house brands) and they are made by various companies out there. I'm not sure who makes Napa oil for them, or if they even have the same oil sold in UK or Europe as in NA--could be made by someone totally different even under the same label/bottle/drum/brand. BITOG is probably the best place to search who makes the oil but again be aware that an answer for the USDM might not be same as for Europe.

In any event, as always, use an oil with both the correct grade and oil spec. for the vehicle. If the Napa stuff meets those you are fine.

 

5W cold side oil should be good. Even 15W oil is pumpable at -24C, you shouldn't see that cold on the islands you live in. Yes, even some 15W oils are VAG approved (old 501 approval, but still)