UBB.threads PHP Forum Software Community Forums UBB.threads Version 7/8 Support PayPal button

Hello all!
I have a question and need help, I would like to add a PayPal button on a restricted forum such as this one
http://sundance-communications.com/forum/ubbthreads.php/forums/57/1/Telecom_Leads_-_System_Sales_a
so that we may sell subscriptions to the customers that do not have access to this forum. I was able to add the PayPal button to the login page, but I am not where this PHP Script is or template and what it is called.
" Access denied to this forum. This forum is either restricted to a certain group, or you may need to register and login in order to view the posts within."
Plz, any help would be great TY!

Unfortunately I haven't really used the Subscription Groups feature (which would allow users to pay via PayPal for inclusion into a group), so just a simple search here would give you about all of the information that I'd be able to get access to.

I'd mention the Postcount Groups article on wiki, but the settings there would have little to do with a Subscription Group.