Bella Corse has 'em.
http://www.bellacorse.com/bce059.htm
There's been some trouble with their clutch cables, though.
A search would probably turn up some info on that.
Before I ordered from Barnett, I inquired as to whether the problem had been addressed.
The answer I got was that there have been no changes.

Hard to say about the Barnett direct thing.
I think some folks have gotten brake cables direct from them.
I called them about that and a lady answered and declined to sell direct to me.
That didn't matter, 'cause I was after the universal Goodridge stuff which isn't hard to find.

For the clutch and throttle, I was told by someone who'd been through it to call and ask for Mark Bowman.
I think there's also someone named Mike that can take care of it.
Maybe they don't wanna fool with int'l?
Dunno.

Another thing I don't know is if it would cost any extra to go through an alternate source as they recommend.

Said Molly to James, that's a fine motorbike. Richard Thompson