You need a standard zero offset trailer wheel with a 6x5.5 bolt pattern. There are plenty of places on-line you could buy from. I would be happy to quote you if you PM me.
CUSTOM WHEEL & TIRE PACKAGES
$125 LED LIGHT PACKAGE - FREE SHIPPING
REBUILDING HOLLEY MARINE CARBS - $249 DELIVERED
REBUILT COMPLETE MARINE HOLLEY 4160 CARBS
FOR 302, 351 & 454 STARTING AT $425
Email - firstname.lastname@example.org