This is what I found in a general manual for Ibanez basses, 2009 at their site.
http://resources.ibanez.com/resource...s/bass2009.pdf
4 String Basses .045, .065, .085, .105"
5 String Basses .045, .065, .085, .105, .130"
6 String Basses .032, .045, .065, .085, .105, .130"
You could also use calipers to measure the actual gauge of each string.
Any normal 6 string set for a long scale bass should fit.