Umm,

You can go to Revolution racegear or Race& Rally in Greenacre to get proper roll bar padding.......

but to get cheap stuff that work well, give your local shopping centre refridgerator mechanic a call. You can get it for about $7.00 a metre although you can't use it for racing (CAMS):P

Any 4 x 4 store.

super chaep auto near my house has it, maybe one up there will too ?

Any Rubber shop such as Clark rubber

i use copper insulation
u know the stuff from water pipes that stops the from bursting