Unrelated question but I see you're probably located in Europe. Are there any places around to get your PCBs treated with conformal paint ? And I mean tiny runs - couple of PCBs.
It's usually an options at the assembly house you use, bundled with the pick and place and soldering process.
Honestly it might just be worth doing it yourself if it's a few and you only need something like acrylic. Use a good flux off and degreaser, get the board spotless, and use something like this https://no.rs-online.com/web/c/facilities-cleaning-maintenan...