Just found 2 oz 10 ct diamond sprays made by Richmond (?) for $16.95 per bottle. Thought I’d pass it along in case you’re interested. I don’t know anything about the Richmond company; does anyone?
https://www.chefknivestogo.com/dispandpa.html
Then this website sells the HandAmerican diamond sprays for $21.95. Same thing, 2 oz, 10 ct.
https://www.bestsharpeningstones.com/product_details.php?category_name=Micro%20Lapping%20Film&product_id=188