I use Uo-Chikyu by Hiroshima Files. The set I have are .010" - .056". They are double edge (same size each side - not V shape).
FWIW, you can easily and safely gain up to a couple of thousandths on each size with the right technique. I will reiterate that practise and experience are important, as with all this stuff.

IMO it's worth buying some cheap nuts off Aliexpress or Amazon just for the purpose of having a go and not worrying if you totally hack it up. And if you don't ruin it, you may just have a nut for another build!