Fireproof underwear price vs comfort

[Bebbetufs]

Do you have any advice for what to look for when buying my first set of fireproof underwear? There are no racing shops here, so I will need to order online. As such, I'm unable to check out the differences in quality and fit before buying.

I'm wondering what the differences in price and fabric entail. I won't use it much, so looking to save money, but I don't want to sacrifice too much comfort either. Are different fabrics warmer than others? I'm in Norway, so the temperature wont go above 28C/80F, but staying cool is always nice.

I need it to be FIA certified and as such I assume the level of fire protection will be similar across brands and price points. Where should I "level up" and where can I focus more on price? I'm thinking socks and balaclava can be affordable, while spending slightly more on trousers and tops may be worth it.