Thank you for that very useful info!
I contacted Nervous Waters fly shop which is close by my hotel in Waikiki and will be stopping by to pick up some wading socks and flies.
As for casting, my guide says his rods are overlined and front heavy to make it easy to cast. I just don't have the coordination to haul or double haul so I am going to rely on spey casts with a SH rod.
BTW: Instead of carrying the spey rods as checked luggage, it was cheaper to send them via US Postal Priority which I just mailed out to my hotel. After the trip, I have a return label for them to ship back to me.
Will hopefully report back with a trip report.
Spey casts are unlikely to be very effective for sight fishing. Not fast enough to get the fly in front of the fish, and the noise of your D loop ripping out of the water is probably going to spook any fish you are close enough to cast to. Having said that, I have never tried it, so maybe you can find a way to make it work.
There are spots on Oahu that you can blind cast for bonefish. Spey rods might be more effective for that.