Unfortunately, Michelle was no help. She said that:
"PROIV has elected to include the SSO functionality as part of standard distribution of the PROIV product effective with the Version 8 release. As a result, the SSO’s are no longer available for resale separately and they would only be available if/when Version 8 is purchased.
I assume that you are aware that Version 8 was successfully launched in December 2014 so the best course of action is for you to to contact your respective account manager to further discuss procuring Version 8 if you require the SSO functionality as your account is out of my territory. "
As far as I'm aware this is incorrect and the SSO functionality will only become available in version 8.1 which has not been released yet. This means the SSOs are not available at all at the moment.
I can't help wondering if NGA are aware that the SSOs are a very useful way to extend ProIV so they have packaged them up as part of version 8.1 in order to make version 8 a more attractive proposition.
We have been asking NGA about the availability of SSOs for a couple of years, since we started using the email SSO provided with version 7, and they never told us what was available.
I would be very interested to hear anyone else's experience in trying to purchase SSOs.