Walmart.com has Nexus 6P for only $304.16.
I know it's an old phone, but it's a good phone. Besides if anyone want to take an advantage out of Sprint FREE 1 year offer, I would go with this phone (assuming you don't have any eligible phones).
I bought this phone for Sprint only in September for around $360 plus tax from Walmart.com. and now they automatically adjusted my price and refunded about $60.