Anyone know where I can get them? I'm not gonna give up .012s, but I can't find any electric strings higher than .011s, and I can't find any acoustic strings at all.
Why not get a regular set, and buy the low B in bulk from an online place like juststrings.com? Or buy all in bulk whatever gauges you like. That would be a good option in my mind.
As far as figuring out what you want, add .010 to your E string, then buy a few different ones that are close to that number and just see what works best.
BTW, do you have any pics of your guitar? I've wanted an acoustic 7-string since I heard Dream Theater's "A Change of Seasons".
Ah, I was just gonna make one of my 6-strings B-B. Either my LP-100 or my Jazzmaster that isn't assembled yet. (I use acoustic strings on all my electrics.)