You have a decent set up there with a 50s RW p bass and 700RB. What cab(s) are you running the RB through, if it's a 4x10, then 2x15 would be a natural progression to give more punch, although some 4x10s can be very punchy. I'm guessing you are looking to be heard more in the mix, but if you don't have a sound or tone in mind, changing pickups doesn't seem a good way to find the tone you want. Different strings will have a greater impact on your sound than changing the pickup.
The value of the capacitor will make a greater difference than the brand. Orange Drop are good caps, a 0.1 cap cuts a lot of high end, leaving lots of punchy low end, the standard 0.047 cap sits in the middle, has less low end than the 0.1 cap and more high end, or a 0.022 cap (which is essentially a guitar cap) lets lots of high end through, and less low end.
Having a light touch may be the issue with you needing more punch, so a hotter pickup (something around 14k) would be a good way to go to, the obvious suggestion would be a Seymour Duncan Quater Pounder (SPB-3).