The Bronco pickup is a Fender Musicmaster/Bronco/Mustang/Strat-sized guitar pickup. The rout is a bit bigger to allow adjustment and ease of assembly.
The standard upgrade so you don't have to do any routing is a rails-type Strat-style humbucker. This will get you a good round tone, depending on the model.
As for the Rickenbacker pickup, I have an HB-1 in my custom P-style bass. Will it fit as-is? No. You will need to rout out the body to make it fit. You will need a pickguard made if you want it to stay neat, as the adjustment screw holes on the pickguard are wider than the HB-1, which uses in-board screws. I modified a friend's Mini-Strat for Rick pickups (they are all the same physical size). I had to rout that body as well for the pickups to fit. He didn't want to get a new pickguard, and, well, it shows. However, if you are up to the task, and the Bronco has the narrow bridge (narrower than 2 1/4 inch "Fender Standard" on P's and J's), then yes, the HB-1 would look good and sound good.