Facilitating crowdfunding platform under a non-US company

Hello all,

I want to launch a crowdfunding platform under a Hong Kong registered
company.

It seems that the major players that could help me facilitate the
crowdfunding functionality don't support Hong Kong based companies.
I checked so far: Amazon Payment (only US), wepay (only US), BrainTree,
Stripe.

So far it seems that my only way to go is with paypal's chained payment API.

Do you know any other service that might help? I don't mind testing
experimental APIs or checking non-trivial solutions.

Thank you very much,
-Daniel