Sorry for the delay, I was on the "Internet-free zone" for the last two days.
Matt is right, the front wheels of my Isuzu are WRP Halibrands, part# W-06.
WRP also makes matching rears.
Rear wheels in my Isuzu are ProTrack Centerlines, style G.
Guys already mentioned NCP Hobbies, Fast Eddies & TSS.
E-Slotcar also carries these wheels.
Halibrands top row, second ones http://www.e-slotcar.com/catalog/569
Pro Tracks, .300 wide. You can get them .435 and .500 wide too. http://www.e-slotcar.com/products/6012