I've searched and searched and can't find another watercolor set quite like this one, or a maker of antique watercolor sets in St. Louis. However, it seems that George Osbourne, one of the few 19th century American makers of artists paint (and deemed as good as the British) produced watercolors embossed with eagles, as these are--with the ones I've found dating the 1830s. I would think based on the color litho lid that these came at least a few decades later (the 4 rows of stars on the flag would suggest pre-1848, but not sure that’s an accurate indicator.) Clearly they were specifically made as a child's set, and apparently just for boys:(

There appears to be one paint block missing but the rest have never been used, and represent a really wonderful, nuanced palette. There are two porcelain mixing dishes included, which have come unadhered from their designated corners but are in excellent condition, and a paintbrush, which definitely shows some use. I tested one block from the underside and the color is beautiful. But also a lovely thing just to set somewhere, and I'm learning that these antique sets are very dear and hard to come by.

Box measures 10 3/4" l x 6" w x 3/4" t. Slide top slides on and off just fine and holds closed. There are a couple of old horizontal splits in the lid and on the bottom that were glued back together long ago, requiring one just be a bit gentle with the set.