JLP, yes Prawn/Chokka is a great alternative to natural baits like Sealice, if they're not available. It's my favourite bait for Natal edibles.
As far as hooks go, anything from 3/0 to 5/0 will work. In fact, we recently caught Stumpies with tiny hooks, like the Daiichi DH55's on a no-swivel trace.
Nowdays each brand name has it's own sizes

a 5/0 Gamakatsu Soi Ring is smaller than a Mustad 4/0 BigGun...

Small hooks catch all sizes, big hooks only catch big fish...
What's important, in my opinion, is a Fluorocarbon Hook snoot and a cone sinker that can move around with the surge and current.
Also I always use flotation inside the bait to keep it off the floor and increase movement.
