I'm another fan of the non-dedicated pack solution: if it looks like it holds camera gear (either by nametag or by its lumpy design), then at best it will hold gear in the basement, or perhaps on a dedicated project (theaterwork), but not in public.
My favorites are the MountainSmith Lumbar packs, and you can buy shoulder straps for them, as well (aka 'strapettes'). I've carried up to 15lbs comfortably all day in the
Mountainsmith DayPack. Buy some name-brand inserts to fit your gear, and you're set. And if, in preparation, you drag it behind your car for a ways, it will look aged and people will think it holds nothing more than an old fleece and a used Nalgene bottle, which is the way we like it.
If waterproofness is a higher priority, you could go with a waterproof roll-top bag inside the main bag, or... I have a large fanny-pack... er... derriere-tote... that is waterproof by design:
WxTex; there are some nice looking packs there, as well.
Well, I look at what I wrote here, and then back at what your request, and it's clear that I've failed to answer you directly, but perhaps it will help someone else who's looking, or help you think about some other options....