This might not be the most helpful for balls and gloves (though I do see golf ball deals pop up at least once a week), but golfwrx's classified section is a great place to get deals on a lot of stuff. I got my AD-DI shaft there for $130, along with my KBS shafts from 3-LW for another $150 for the set. The AD-DI was used for a week (didn't have a mark) and the KBS shafts clearly only ever had a grip installed on the 7-iron. Good deals there, at least from what I've found, but mostly on clubs and shafts (though they do have golf balls in their classifieds every so often).
The nice part about that is they also have a WTB forum, where you post what you want and people come to you. That's actually what I did for the iron shafts. I posted about what I wanted and I had about 7 responses to choose from within 24 hours, so it's pretty active. For golf balls other than ProV1's that would be your best bet for finding them.
I know how this is going to sound (Oh no, Shane's asking another set make-up/gap analysis question. Ahhhhhhh! Let's run and hide!) But it's a very valid question...
I hit my 3 hybrid pretty well, (I finally stopped pulling it) but I believe it's too close in distance to my 4-wood (225 vs 215). My 4-hybrid is around 200 ish... ( I have a little gap down to the 5-iron... frankly because I just don't hit it much) would I be safe to drop the 3-hybrid?
I thought of carrying both a 5h and a 5i to fix the "gapping issue" but I usually just grip down on the 4h when I'm between the two...
I understand it drops me to 13 clubs; but the other alternative is to drop the 4- wood but that creates too much of a gap.
Things I do when the pace is slow:
Take more time on my shot
Engage in casual conversation
Look around for lost balls
Doodle around, looking nonchalant
Stare at the front group, trying to use force to move them along
Jeez, I used to have a whole list of them, but can't lay my hands on it right now. One name I do recall was Hurricane Golf. I believe they were based in Florida. Maybe just Google something like "golf discount outlets" and they could help you out.