I have a custom made 20" Bolder Nitro DC cable w/2.5mm barrel connectors on each end that was made to fit a Trends UD 10.1 USB transport and a Channel Island VDC-SB power supply. This cable would work well with a SB3 and Channel Island VDC-SB power supply or any other power supply that has a 2.1mm pin jack such as the KingRex power supply. It's a $125 high quality DC cable that I'll let go for $60 plus shipping. Same cord that's in this picture but with the same barrel connector on both ends (w/o the larger XLR connector).

Cheers,
Robin