Not used Bogen, in the Valcom world you would use a V9940 Station level page adapter, telephone line in/contact closure out, connected to a V9927A Multi tone generator, contact closure in to the appropriate tone connection and tone output to the paging system input.
You can use a standard analog line for this option.
On the Valcom V2006 (for example) there is a built in tone that can also be used, you would just need the V9940 to provide contact closure to the right pair on the paging system, the Bogen may have similar.
Hope this helps.