Yes you can buy them with internal bi-wire. Cable has 14 conductors and bi-wire cable and single wire cable are the same, just split up different at the speaker end.
It may be cheaper to buy used 2nd set used here for double run as opposed to sending back to factory for internal bi-wire re-termination. There was a post here recently about the outrageous charges some companies charge for custom cable work. Even if they are close to the same price get double runs, gives superior sound quality.
It may be cheaper to buy used 2nd set used here for double run as opposed to sending back to factory for internal bi-wire re-termination. There was a post here recently about the outrageous charges some companies charge for custom cable work. Even if they are close to the same price get double runs, gives superior sound quality.