Proozy offers the Birkenstock Unisex Madrid Birko-Flor Sandals in several colors (Toffee pictured) for $64.99. Coupon code "PZY50" drops it to $50. With free shipping, that's the lowest price we could find by $9, although we saw them for $10 less in December. They're available in select men's sizes from 7 to 10.5 and select women's sizes from 4 to 10.5.