Choral octavo size plain paper?

[JimEvans]

I'd love to print my sacred choral work on paper roughly the same size as that used by commercial publishers. Where can I find it?

[CHGiffen]

I doubt that you can find it easily, if at all. It's not plain paper. Publishing houses print on larger paper that is folded and trimmed.

I'm assuming you mean "Choral Octavo", which is about 6.75" x 10.5" (there are many somewhat different Octavo sizes). So, probably the best solution is to print on a standard size (Letter or A4) paper, suitably reduced (if necessary) and preferably with crop marks, then use a paper cutter to cut pages to size. This is what I do.

Chuck