I just looked at the boots on my RT. There are two differences, both of which you can work around. The hole for the antenna is larger for the CB so a drill will easily fix that. There are three notches in the tupperware on the edge of the hole. The two top ones look to be the same on right and left. The bottom one is left of center on the left side, and right of center on the right side. You could modify either the boot to remove the interfering rubber with an xacto knife, or cut a new notch in the tupperware. I didn't double check, but the angle between the antenna and the body may be a problem, but looking at the two boots side by side I don't think so.
If the boot doesn't cost much, and you're having too much of a hassle getting the correct one, why not try making the radio one fit? You'll be out a few dollars is all.