Get a regular sized surfboard shaped for you by a local shaper in EPS Foam and have him put a heavier glass job on it. The weight gain in glass will be balanced out by a lighter core. If you head into to the surfing forum there a couple of posts about surfboard shapers in WA souple of the guys in there can point you in the right direction.

As for straps the NSI or Surftech strap pads seem to work pretty well.

Edit - you can go the Jimmy Lewis route to he makes a nice board

Airush converse. Was tooling around on Kitehard's (Darren's) kiteshop website the other day and noticed he had a second hand one for $450 under the second hand boards section. Think it is called Aust Kiteboarding School, the link is on this site somewhere.

I picked up a second hand one in mint condition for $500 recently, pretty happy with it. Bit heavier duty than a normal PU board so expect it will last heaps longer at high speeds of kiting in the surf / chop.