I'm from Europe. Got this reply from AMG factory :

Dear Mr. ______,

thank you for your interest in our website and in the products of
Mercedes-AMG.

I regret to inform you that Mercedes-AMG is an exclusive contract partner of
Mercedes-Benz and therefore we are not offering any products for other
models of the DaimlerChrysler Group.

Furthermore I would like to inform you that Mercedes-AMG is not a tuner but
an engine constructor and is not offering any retrofitted tuning kits. We
consider the vehicle as an entity where you cannot just increase performance
without adapting accordingly brakes, suspension, exhaust system etc.

In case you have any further questions, please contact your local
Mercedes-Benz dealership which should be able to provide you with additional
information on Mercedes-AMG and our products.

Best regards

Kerstin Heiligenstetter
Mercedes-AMG GmbH