And ideas for proxying existing SOAP-RPC services in 7.1

Hi there, I have a bunch of existing webservices built on 6.1 (with planned migration to 7.1). Due to a company merger I need to expose them to a new organisation but the new organisation is restricted in terms of which services it can access due to netork restrictions - it can only see a sub set of all my IS.

I would invite suggestions on ways to achieve this.

What I was thinking I could do was create a proxy service to route the requests to appropriate endpoint based on an indicator provided by the client - such as an HTTP header. By doing this I avoid the overhead of examining the XML.

         /  services A-F

– services G-S
\ services T Z

Other thoughts were:
creating a custom SOAP processor, but this seems to be deprecated in 7.1
use the reverse proxy however for my organisation the number of internal servers would be very high and I can not think of a way of doing the content routing.