This?
Basically you can make any cable if you have the right connectors, a piece of cable and a solder iron.
And yes, you can get 2 cheap B6 chargers for the price of one dual port. When you are going for the B6 chargers, be sure there is a power adapter with it. Many of them are sold w/o a power adapter unless you have a 12v high power 12v power supply. And keep in mind the real cheap version is just a Chinese copy which quality is debated.