Regina actually had 4 different gruppos in 1992 -- America, Strada, Stelvio and Enduro. 6/7 speed indexed across the board. Think they were a pretty dismal failure for them.

Right around the same time is when Campy switched to 8 speed cassettes, and their own chains. This may have been an attempt by Regina to diversify/survive.

I have a pdf of the 1992 catalog I'd be happy to send you.