Currently, Stingray does not provide Role Based Access Control that extends to limiting configuration elements. You can restrict which parts of the configuration system a group needs access to, but not which vservers/TIP/Pools/etc that they can administer.
The best solution Stingray could provide currently would be to use either:
Use separate Stingray instances where you need separate configurations or
If this is a service provider style setup, you could build a configuration view inside your own web application, and configure the Stingray using the SOAP or REST API. This would allow you to provide this level of access control within your own web application..