I did not receive an answer...I know you can buy just the heavy-duty hinges, but I have yet to find out if you can buy the other components without purchasing the full system, including the hinges.
Edit: I did find this on the MORryde website:
Jeep Wrangler Tailgate Accessory Tip:
MORryde’s tailgate accessory system is modular, meaning you can purchase and install whichever parts your situation demands. For example, when you’re still toting the factory spare, start off with installing just the hinges for a rattle-free tailgate. When you upgrade to a heavier spare that will fit on the stock carrier, then install the reinforcement along with the hinges. If you go to a larger, heavier spare, install both the reinforcement and the spare tire carrier for optimal reinforcement, both sold separately.
I did not see where on the MORryde site it says the reinforcement is available separately, but maybe a call to MORryde can clear that up...I would love to get the hinges initially, as my tailgate is actually fine with the 32" tire on it, but I am one of those who likes to replace wear parts with overkill parts...