can i use stock 3/4 ton aluminum rims on my srw 3500 4X4?
what is a good after market for this vehicle that can take the abuse?

Yes, the 3/4 ton alloys will work. They are 6.5" and the factory steel wheels are 7" As far as aftermarket, you'll need to look at something that has a decent load rating. I would stay away from cast alloy wheels. Look at Alcoas or Welds. They are both forged and offer exceptional load ratings.