Where to get heatsinks for JL 'slash' amps?

I have a few JL amps that i got off ebay, used

great prices, all working, but a few of the fins on the heatsinks have snapped off

would anyone know where i could get some replacement fins from?

some failed amps might be my only choice?
I'm from australia, and we don't have a dealer/repairer any more due to poor service/support.

Unless i get some custom moulded off my existing good ones >_<