just buy some same size shocks-- most of the 1/8 buggy shocks work, they dont make much of anything for the slash yet!...
aluminum... and or bigger bore are popular and work awesome!! help to really absorb the bumps!
i just bought some aluminum ones from rcmart!! i got some 90mm for the fronts and 110 for the rears... i measured the stockers and it was like 86mm and 106mm(my rears are modded with TI shafts)... the bigger the better!!