So I've unfortunately hit the end of the copy of Galerie des Modes from Bunka Gakuen (I would have been linking to the original page each time I posted, but the site is not set up to facilitate that). All is not lost - they have a second copy of the entire thing! But. There is a but.
The second copy, which is where I've been getting the color plates from, is not perfect. I think it's a reprint from the 1910s. There are inexplicable omissions (inexplicable because I don't even know what the plates are of - I can just see from the table of contents that some are missing) and, most irritating of all, some amount of the original long descriptions have been replaced with text from Louis-Sebastien Mercier's Tableau de Paris. I can't be sure how frequent it is yet as I've only translated the first couple of books. Tableau de Paris looks to be an extremely good source for historical context, but it lacks what I consider the best parts of this project: directly labeling parts of the image and giving explanations for unseen or ambiguous attributes. I'm going to continue translating, but I wanted to explain what was going on first so it didn't look like I'd just gone mad and started translating something completely different instead.