This time being offered by Mike Zee in Denver. The Marketplace listing is actually close to my house. He is offering dumbbells for $1/lb.
The price is a little steep, but they certainly appear to be in good condition. This is also evidence that I should see plenty of these around and would be able to add 2.5 and 5 pound plates to my collection.
I just saw this one listed 7 weeks ago. A little cheaper, but very similar. The smaller plates do not appear to have any markings. Brian Tetreault in Thornton. $100 for all (3) pairs. 130 pounds.
Scrolling back, I also saw some ROC-MO listed back in December 2021. These were again Pro Style dumbbells.