On-one own brand or their Carnac equivalents. These vary from £16-25 and are properly good quality lids; I’ve a white Carnac enduro style one for winter rides (it’s less vented) and recently bought the missus the On-one standard, which looks very much like a Fox Flux. Much cheapness and very well made.
Whilst these are cheap and fit well, I found them very hot (the Enduro style), and the non-adjustable peak is set really low and interferes with my vision.
However, I recently bought one of these….though they re a bit love or hate on the design front.
An Urge All-M. Fits like a glove, very light, well vented, and only £35 including postage from Alltricks.
For some reason it shows as €39 on the site, but comes up as €33 in the shopping basket.
Orange Urge All-M on Alltricks