Necroing since it's still a good idea... -- I'd have a special quiver that only holds 10 arrows and has a second bottom in which the balm is. To keep action economy the same you'd spend a move to activate the quiver (i.e. pull a thing that opens the second bottom, similar to how you pull out those plastic thingies from toys with batteries) and then the standard to press down the arrows into the balm. By the time it's your turn again you're good to go.
For an extra 200 gp they're already coated with ghost salt (which is compatible since one is a blanch the other a balm and it's useful if you don't have a +1 bow already).
Alternatively for 400 gp we can have those 10 arrows be magical +1 (thus not needing the ghost salt blanch) and getting more damage and to hit (again unless you already have a +1 bow).
If you're really desperate for damage you can add undead bane for another +1 cost (including masterwork that's 175.05 gp per arrow), which adds 2d6+2 more damage and +2 more to hit.
1780.5 gp for 10 arrows (+1 undead bane and Holy weapon balm) totalling +3 to hit, arrow-base (i.e. 1d6 or 1d8 + str if comp) + 2d6 + 3 + 2d4 (let's ignore the additional 1d4 points of damage the following round since the enemy won't fail their DC10 Reflex save) => in the ballpark of 9 to 32 damage each!
It's a bit like combining a nerfed version of holy ghost touch and bane for the price of just bane. - plus sucks on action economy side... so I guess it's fair enough.