I found /r/abrathatfits through a acquaintance's blog about a decade ago and this calculator made a huge difference in my life. I did not know that bras could actually be comfortable and supportive.
Yeah, I resorted to custom ordering Ewa Michalaks (which sucked because at least back in 2012/2013 their QC was awful) or just tailoring the bands. I have no depth perception, so you can guess how good I am at sewing. (Hint: I am terrible at it.)
Edit: Oh, but Comexim is a decent option if you're a 26. They do custom sizes like EM, but their QC is much better.
Comexim is the only brand I've found that's close-set enough for me, but I usually do wear Panache bras. My Ava and Roche are in very heavy rotation, and even if the gore on Claras stab me, they're so pretty...
I love that I can do complex math, speak multiple languages, etc. but ask me to thread a needle and I'm like 'that'll take an hour you better sit down'.