after what I understand on the 57mm family the mk2 and mk3 (ex mk110) the turret housing is similar. And after I understand Stockholm class have mk2.
yes most guns are modified for different navy's, so yeah there should be some difference. just like the 152mm you posted in bellow deck... (Is that version the Swedish or?)
What I think I can do is to have Swedish made equipment/weapon on one line, and in the line next to it I have international version of them.
That can give us this look: