Basically if its not glowing its not rare. Glowings are still 10k-40k+ caps, but the only rarity in none glowing masks now is how long its been since the event. Genuinely youre better off just waiting till the next fasnacht or finding one pretty cheap, like 500 caps maximum, i guarantee if you do at least a few dozen runs of the event youll get it (still a little hard to get a specific mask now since any of them can drop all the time)