Zenni will ship you a PD ruler for free and I think has a pdf of one.

I still get eye exams at my Dr. I make sure they send me with my rx including PD.

I feel like, even on non-anonymous platforms, the onus is on a prosecutor to figure it out. Moderators should do their best effort but it is an impossible task. Would you hold a mail carrier liable for what they deliver?

Prime Hyrdration seems, to me, to be the one popular amount kids. It contains zero caffeine.