adding to the web site template list

Is there a way to deploy new web site templates internally? We have a support structure where we coordinate with multiple suppliers for our customers, so our tree contains multiple web browser sessions for e.g. Cisco support and DNS registrars, each with different credentials.

The existing session/credential mapping options don't match this use case very well:
- shortcuts don't allow for setting different credentials on the links; a credential change in one of the locations changes them all
- user-specific or machine-specific overrides don't work, because each group of people need to support multiple customers
- creating a session with sub-entries, and overriding the credentials on the sub-entries works, but it does require us to maintain a separate tree structure for each support site. We would prefer to have the suppliers for each customer listed in the customer subfolder, not inside a generic "suppliers" folder

What we're now doing is providing a template entry for these sites. That works, but it would still require removing all entries and recreating them from the template when a supplier changes its site (which is hopefully rare). Re-applying a web site template on an existing entry would make that a lot easier.