Take your truck to a toyota dealership. Your rims are from the factory, so you can order the caps from the parts dept.
Good answer... :clap:This subject comes up every once in a while over at CustomTacos. The problem (always - so far ...) has been that Toyota remarketed the Enkei rims with Enkei center caps (not Toyota caps). In prior such situations people in your position have found no help through the Toyota parts department, because the wheels aren't a Toyota part.
For the most part, Enkei rims were bundled into region-specific packages (e.g., the SST package in the Southeast sales region; some 'Texas Edition' package(s) in the Gulf Coast region). Because these are regional packages (as opposed to factory packages), Toyota doesn't often support them with replacement parts.
To the best of my recollection, your only recourse is to directly contact Enkei (who don't ever mention replacement center caps in their catalog) and / or haunt eBay hoping to get lucky.
You can also scan the 'Net for recyclers who specialize in wheels / hub caps / etc. Some of these wheel-specific recyclers maintain an inventory of center caps, but (like eBay) it's anyone's guess whether they'd have any for those particular rims.