Shock absorber rubbers


Hi all ,need new rubber bushes for my shock absorbers fitted to Rocky F80 (fourtrak) 1986 2l petrol swb. The shockies are Monroe gas Magnums in good order except for the rubbers. Any ideas on where to get replacements? Have the serial no.s for them. Needed for m.o.t. so please help if you can..........cheers Griff Wink