2008 looking for poly shackle bushings

I am looking to replace the rubber bushings on my rear shackles. I installed Toytec shackles in the rear and was told the rubber looks worn. If I'm going to replace I thought I might as well go with poly. I am also getting a squeak. It is NOT due to the bed mount bolt rubbing it. I have already checked this out. The shop has packed the bushing twice with grease. The squeak goes away for about a week and then comes back. He tried packing it with marine grade grease with the same result. Everything is torqued to specs.

I have tried searching the web and am having a hard time locating some that are specific for my application. Would anyone have a direct link to suggestions?

Thanks everyone

 

Not sure if I understood correctly but here is a link
https://shop-coachbuilder.myshopify...urethane-bushing-kit-rear-leaf-spring-eyelets

 

I actually think you nailed it! I looked at Coachbuilders site and had no luck finding it. No idea why, or what I was doing. Thanks!