Just bought some center caps on eBay (they were listed as fitting Camry, Highlander, Sienna and Prius) for my 2013 Gen3, which I bought Certified Pre-Owned 2 years ago. The center caps are Toyota, with the emblem on them, but don't seem to fit. Indeed, I went back to my papers from when I bought it, and "wheels mounted" is listed in the Carfax, but the center bore seems to be 54.1 mm as listed in the specs I found online (I am not yet allowed to post links, with this, my fourth post, I may be allowed to) they list Gen3 wheel center bore as 54.1 mm.
Pretty sure the center bore specs are for the actual bore of the wheel aka the inside that sits against the hub, not for the outside which is much smaller.