Look at the different color index rings and notice the different spacing on the teeth, they all differ alot. I can tell you I've tried almost every one of those 7 speed freehwheels with the blue insert, they don't work. Then I read my Sutherlands,(should have done that first) notice they stated the only 2 freewheel combinations that work well.

I tried this on a Slant parallelogram Athena :
Blue index ring ( has no mark):Campagnolo approved Regina 90-S 7 speed (marked with <C> in diamond inside the threaded Portion that threads with hub)

Green :stamped A7 : Shimano SIS