Ok, you're doing some AJAX requests, which should reach out for external servers; but instead you want them to be requested from AEM and AEM should act as a proxy to those external servers. Is that correct?
No, I am not aware of any default proxy components you could use. It's a quite specific usecase and it is very hard to implement it in a general way, as you always have the risk to create an open proxy. You could implement a rule on the loadbalancer or a HTTP webserver (like Apache httpd) to forward these requests directly to the other servers instead of AEM.
My question would be, why these 3rd party requests should be made to AEM instead of the other servers directly.
Kind regards,
Jörg