Again given the nature of the monk, I won't even bother investing in triple formless chain... he's only going to do sleepers for zeny and nothing else anyway. Get a formless chain only if the monk is going to join the "usable character" crew instead of a support char towards funding.
I'll personally get 12 int for a 12% boost which is pretty decent for sp recovery items. Once you got yourself a "satisfying dex" then pump the rest to int, leaving both agi and vit at 1. This sounds totally crazy and absurd, but it works *IF YOU ARE STAYING AT SLEEPER ONLY* and nothing else. (fish handles everything if you're only at sleepers)