Cristina from Stripe here.

Stripe just launched in beta in the UK and is available in Canada as well, whereas I believe Balanced is only available to users in the U.S.

Many customers with international buyers and sellers have opted to use our Stripe Connect product for that reason: https://stripe.com/connect

Braintree is one of the best international payments option around (aside from PayPal, but PP has it's own host of issues). I'd also encourage you to check out WorldPay. WorldPay's underwriting process is pretty brutal from what I hear, but their international reach is impressive

http://www.worldpay.us/