I love Pura Vida! You can purchase their products from puravidabracelets.com for 50% off your entire order, and they have a really expansive selection compared to Birchbox. If you can't find the coupon code online, let me know and I can email you a referral (you can also get $20 for referrals fyi).
As a student, I try to save as much as I can, but somehow I feel less guilty buying stuff that donates a portion of their proceeds to charity.
P.S. I don't work for Pura Vida or anything.. heh. I just love their shit! I don't wear any other bracelets, really.