Ask HN: Micro-payment processor for online games?

We are looking for a replacement for our current in-game virtual currency payment processor, Superrewards. This processor handles the in-game currency transaction on behalf of us and pays us a monthly payout. This way, we avoid the entire hassle of sales tax / vat / invoicing / accounting. Superrewards announced today that they are shutting down in 6 days (!). Are there alternatives that offer a similar service?