Putting together a varminter-type rifle and looking for an aluminum free float tube that also has the QD swivel.  I've been poking around the internet trying to find the individual tubes from RRA, Stag, etc. but I'm not having much luck finding exactly what I want, so I was hoping someone that has one can point me in the direction of theirs?

Just to clarify my requirements, solid rifle length tube with a knurled or smooth finish, no vents and a QD swivel.

Sub'ing I've been looking for the same thing.  I just want an inexpensive tube with no frills, no rails, sharp edges, etc...  Seems like they're few and far between unless you want to buck up for a carbon fiber glued together / cut to fit set up and they certainly aren't cheap...

In general, the QD mounts are designed for picatinny rails.  There are some that are designed for Magpul type items with slots.  You can possibly mount something like on the site below if you have clearance on the tube.

Impact Weapons