Although Google Checkouts is shutting down, Google Wallet for Digital Goods still lives on (https://support.google.com/checkout/sell/answer/3080449). It offers pretty much the best pricing on the net (most favorable of 5% or 1.9% + 30c (USD) per transaction is automatically applied.) and works in way more countries and currencies than Google Checkout ever did (https://developers.google.com/commerce/wallet/digital/faq).