Want moonlight for when go to sleep at night, so can find it if needed. Zebralight is the obvious choice with it's best of class regulation, but expensive just to sit around not being used.

Can buy tritium vials over the counter here in the UK.

Also have betalight torches (large coin sized tritium source for map reading and the like), but have gotten really expensive especially new.

Link: https://www.betalight.nl/en/outdoor-tactical/torch.html