Beal Static Cord is also available on a 120m roll. If you need a lot, buying it this way this saves quite a bit of money as we don't have to allow for wastage and we don't spend any time cutting it.
2mm and 3mm are definitely not for climbing and 4mm should only be used with caution and where nothing bigger will fit.
5mm is OK for Prusik Loops and other static use (such as abseil tat) as is 6mm.
7mm and 8mm are OK for rethreading chocks.
Beal do not make a 9mm cord (what we sell as 9mm is dynamic climbing rope wound onto a reel).