Can any friendly GM point me in the right direction for acquiring the correct bag to use for stowing MK-79 kits in Boat Crew Survival vests?

They should come with one from your servicing armory. If not, the only way I know of to get replacement bags of the same size and shape are to save a few the next time you dy a pyrotechnics exercise.

If the ones you have now are too far gone to wait, I suggest you get a few zip-lock sandwitch bags from the FS's untill you can get the ones you want.

If I had it my way I'd put them all in a Pelican 1020 case but when RFO and STAN Team comes around, the good stuff is too good so I have to use the 'authorized' bags. And when you're talking a couple dozen kits overall continually exposed to salt water...well the bags go bad and look like crap for inspection. I'll ask the armory, though. Thanks.

I don't have the information on replacement bags, but have seen units down here putting an extra ziplock bag over the bags they are issued with to help protect the pyro. The RFO team has had no issues that I have heard of.

As stated above, everyone should save servicable bandoleers, bags, MK31s (turn-in item), and rubber caps off Mk124s after pyro training events. If you dont, You may be able to get these bags through your servicing armory. If they don't have any on hand, This is the man they should call/email:

Douglas E. Stark
Pyro/Demo Commodity Manager (Acting)
Crane Division, Naval Surface Warfare Center (NSWC Crane)
Harnessing the Power of Technology for the Warfighter
Joint Special Operations Response Department
300 Highway 361
Crane, IN 47522-5001
PH: 812-854-2996
Fax: 812-854-2304
Email:douglas.stark@navy.mil

I get the impression this issue hasn't been vetted properly thru the chain of commands.
I don't think Mr. Stark would appreciate a bunch of calls from a bunch of folks. Me thinks you need to work with your servicing armory, who in turn can work this issue up the chain. Ultimately GMCM Jones, the Ammo King, is the person to answer this question officially. Get back in the chain of command where you belong and quit doing end runs.
Tim Knight, GMCM, Ret.