fat sac questions and where to buy?

i have some fly high pro x fat sac questions as it pertains to a 2003 X-2. the boat was custom ordered without factory ballast.

750's in the rear for sure, that's a no brainer i guess, but how about the locker?

i called fly high and they said instead of using the WS704 (generic ski locker sac), to get the WS705 (rear seat sac) and use it in the locker instead. the guy said it would obviously be underfilled, but that i'd be able to get more in it than the WS704.

i'm going to order this stuff up soon and am wanting to confirm this info.

i'll be buying the tsunami pump and doing it old school until this fall when i can afford to have it all plumbed in with pumps and switches.

if there's anything else you folks think i need other than the 3 bags and the pump, please let me know.

any advice and a point in the right direction on where to buy would be appreciated. i'm wanting black.

thanks