MXY pickups for 5-string basses are 5x1.22 inches. These will fit strings widths up to 3.50 inches above the bridge pickup. $480 for a standard set with either 3 controls (volume, pan, filter) or 4 controls (volume, pan, bass, treble).
Custom pickups masters are $350, and the silicone mold is $75. Once they're made, we can make as many of the custom shape you want.
Depending on the value of the bass, you may find an existing shape that can be fit with a minimum of routing to save some money.
The pickups are intended to work with our electronics as a system. We don't so any testing with other electronics, so we don't have experience with mixing them.