Hi all.

What type of buckle is correct for these Suveran's? Are plain ones ok?

 

A plain buckle would be my assumption. The lower two in your picture look good. The branded buckle on top is 70s, more or less.

 

I think the one in the middle is more 40s style

 

To my knowledge the buckle was never shown in advertisements so we'll probably never know for certain. I think I recall in the buckles thread that they were usually branded after 1948?