I got mine from Sunglasses-shop. They were super cheap – £88* inc delivery for Ray Ban Wayfarers with a prescription lens and they came quickly. I’m happy enough and for the price it’s fantastic, although the lens is satisfactory not brilliant. It’s a bit warpy in the corner, and seems a bit prone to scratches. I think they do a more expensive lens option which I didn’t investigate. They unusually included the original RayBan lenses so I can always put them in and sell them at a later date.
Considering the previous set of sunglasses was similar but from Boots and cost more than twice as much, it seems churlish to complain.
*I googled a discount code and found 20% off.