There are so many choices, it's really up to you. Take a look at Partsconnexion or percyaudio
and go for what tickles you.
I like the fancy stuff for cheap. Like 16awg solid core pcocc wire for the AC connections
http://www.partsconnexion.com/wire_hookup_neotech_copper_pvc.htmlDoesn't make sense to spend a whole lot on binding posts unless you're going up
the chain materials-wise ($$), so maybe
http://www.partsconnexion.com/product9694.htmllist is endless.
BUT imho, the best mods you can do for this amp for cheap are:
power cord:
Pangaea's super cheap cords are the rage here and on audioasylum
http://www.audioadvisor.com/prodinfo.asp?number=PGAC14If you're not too green to DIY, I'm one of many fans of VHaudio's DIY power cords and interconnects
http://www.venhaus1.com/diymains.htmlpower supply -- swapping in some larger TS-HAs as discussed in the main thread.
power conditioning -- anything Alan Maher has is a great start. but he's on military tour 'til July : (
http://alanmaherdesigns.com/default.aspxHe's also contributed cheaper DIY methods. I have several of the 193L chokes
and they are the supershiite.

Anyhoos, the bottom line is replace the Shack stuff by a notch but focus on the
AC/power supply. The Class D is transparent enough to reward you for it!