http://www.independent4x.com had them in poly for my 86 Trooper and they looked like a dead on match for the set I had recently pulled off my 79 4x4 LUV. Email them and see what they say, Matt (the owner) really seems to know his stuff and will probably know for certain if they match. I was pretty sure they looked the same size, but the set I pulled off my LUV were pretty well shot so it was hard to be sure. 84-86 Trooper should all be the same, and are more likely to match than 87 and newer.
That got me 1/2 inch of lift back in the rear of the trooper, a lot less rear end "wiggle", and no squeaks. My LUV I used recycled bushings from a 2WD luv, but if I were doing it again I'd order the poly set.