NOTATIO

Most of the chamber music I've been working on as a cellist or engraved has used a page size that sails around the 9 x 12 inches area.
There appear to be many ideas of what "quarto" means exactly, and even just myself have seen anything between 225 and 235 being used on the horizontal axis when 305 mm was the height. For example, Breitkopf calls their 230x305 size "Bachformat" (even if another one calls that the 228.5x305, which is 9x12 in, I guess).
For orchestral parts, some use 240x320 mm, other the "Leipziger" 247x320 mm, and many standards could follow suit.

Since I'm approaching a print run of a few chamber music titles, I've realised that, to fit inside the score, the inserts will be cut by 2.5 mm on each side thus resulting in a score of, for example, 230x305 mm and parts of 225x305. I believe that could be a bit small and am wondering if I should go for the bigger Leipziger (or the slightly smaller 240x320) for the score, and thus that -5mm dX for parts.

Is there any silent rule that says that chamber music editions should be around 9x12 to 9.5x12.5 in and orchestral parts 9.5x12.5 to 10x13 in?
Or is it just a personal preference of each publisher, also according to what paper the printer has in stock (or cheaper to cut)?

Please share your opinion and, if possible, your personal experience.
I believe it would be most valuable for everyone looking to print music on paper!
Thank you!

I don't know if this is standard, but all of my instrumental parts, whether it be chamber or orchestral, have always been 9x12.
All piano music has been 9.5x12.5 (whether solo or chamber music with piano.)

While my orchestral scores have varied from 11x14 to 12x17.

What margin and staff size do you use in 9x12 parts? I'm just concerned that, if they cut 2.5 mm per side, margins will become too small.
9.5in seems to have more legroom to work with, but printers in EU seem to configure their machines on a few sizes and then anything outside that costs more to produce (e.g., if I print 230x305 is one price, if I do 232x305 it is another, higher, price).
Interesting to hear about the 12x17, is it a standard paper in the US? I've only heard of tabloid (11x17) or (12x18, that is double 9x12).