I know a lot of Ray Ban posts on here are for sales at 3rd parties that generally have the sunglasses much cheaper. But I got an email from Ray Ban showing they have 50% off available if you purchase prescription frames + lenses.
I stacked this with the $30 off $150 Amex offer
The email was sent from "Ray Ban The Ones" - the deal is valid until June 10th, so I assume if you sign up for their promo emails you'd be able to get a promo code:
The total for polarised prescription Clubmasters came out to ~$160.
QA Note: Code may not apply to new e-mail subscribers, only existing subscribers, so YMMV.