Drive shaft maintenance

I have an 05 double cab short bed 4wd and replaced the carrier bearing about a year ago, when I separated the rear half of the driveshaft from the yoke I noticed the splines section had a rubberized coating that was deteriorating but looked like it would hold up ok. Now I am hearing a clunk coming from the drive line and I can detect some backlash between the rear shaft and the yoke. I think I need to act on this before it gets worse. Can I replace just the rear driveshaft? Are the front and rear shafts balanced separately? Is there anything that can be done to restore the rubber coating?

 

eh buds I have the same problem with my 2010, I've read people saying glidecoat/glidecote is the nearest to oem coating. What did you end up doing, I would rather just find another rubberized coating locally any recommendations? I definitely won't be replacing the spline or yoke so if I cant find another solution ill be scraping off whats left of the blue coating, greasing tf out of it & prayin that doesn't cause vibrations/spline damage.