Bought a pair online for less than half the price that the high street were charging. My optometrist gives perscription upon request but PD isn't part of this. I was able to measure the PD myself though (did several measurements using a few different mirrors).

Have been wearing the glasses every day for over a year and they're the clearest and sharpest lenses I've ever had. Don't think I'll ever go back to buying from a store.

[edit] For anyone wondering the methods I used to measure PD, I used a ruler in front of the mirror, a ruler in front of a friend and a couple of online apps like Warby Parker's https://pd.warbyparker.com/ The results were pretty consistent so went ahead with it.