I think that at the time when I first saw these they were touted as 2 1/4" balls. It's been awhile so I could be wrong. Their proportions seem a good fit for the box which appears to be the typical SALUC box. I know SALUC made smaller boxes, but I've never seen larger.Another awesome set, Mr B.
The plastic tray with the gulley underneath the balls reminds me of the style used by Aramith in the 1970s and early 1980s. What do you think, sir?
Also, and this is a wild guess, do you think this set might be larger than 2.25 inches and perhaps designed for Russian Pyramid? I only raise this, admittedly slim, possibility as a similar modern set exists. I’ll endeavour to find an image and post it up.