Price: $70 + shipping
This electrical box mount attaches to the bed rack and provides two, separately switched, 12v receptacles. All hardware rated to at least 20A.
The electrical box is weather-proof, with rubber grommets, switch and receptacle covers.
Comes pre-switched/wired, with ~6 inches of 14ga wire outside the box, ready to wire to your fused power source.
Note: requires wiring to battery/power source, not included.