Ok let's throw a few more ideas in the mix...
The Xterra has very similar roof bar diameter( if not the same).

The only thing I can see as a drawback is the length of the cross bar on the '05-'06 Xterra is 32 5/8" while the '05-'06 Renegade is 38 5/8". The older Xterra is wider, but I do not have the number, but not long enough. I keep trying to find something to work as the Xterra brackets are nice and low and clamp in place with a Torks head screw.
Option (1) find out who makes the tubes for Nissan and see if I can get them to make a custom length.
Option (2) Buy 3 from a bone yard and weld them together for the corect length - lots of work and not cheap is my guess plus the aluminum may be a special grade and has an arch for preload.
Option (3) Haven't come up with way to go from the the Nissan bracket to a tube without lots of fab work.
The key is that it is easy to come up with a tube for a cross bar, but hard to mount it so it can take a lot of load and punishment.
Just some more thought starters.
_________________
Frank
'05 Beryl Green Renegade 4x4 (of course)
LOST # FH050887
http://www.cardomain.com/ride/2122009