"Hmm, what about sending the coins to Xapo, and then sending a payment from there? From what I've seen, they seem pretty decent about mixing coins, these days... (I've tried sending myself a few payments back-and-forth between my local MultiBit wallet, and my Xapo account, and I haven't seen any of my local/Xapo addresses in the BlockChain.info taint list, so far - but YMMV)." - Tyson Key