I've also been looking for this. I think, just wait a couple months and stick to paypal. Paypal is going to start offering cryptocurrency and I assume they will allow bitcoin payments too. However, to my understanding paypal IPN because its so simple and easy to understand but it is HIGHLY outdated. I used to use paypal IPN but I am trying to understand their new API which is honestly aids and I am honestly considering to pay someone to code me the gateway