Thank you for the answers!
Please put more pictures in!!! (especially if you have metric trays loaded with SAE: metric have more pegs and would be preferable to me). I am interested in 1/4, 3/8 and 1/2 (I own only one 3/4 socket which found it's way into my tool pile...)
I think I will wait for the next sale and consider buying some - my vintage socket collection is expanding.... I buy when opportunity presents to buy for a very good price only (already have Husky, no-name, random accumulated from before - thus no rush). However, once I got addicted (thank you, GJ) to SO, SK, Craftsman =V= and -V-, Boney, etc. I started picking them up. SO in good condition seem to be harder to find on yard sales - majority come either in poor condition or with PO initials scratched on them...
...I wish you could buy these socket trays in stores - it's always easier to buy things when you can touch them first. (and would be easier slowly adding them without paying for shipping fees...)