The seller "thinks" it's a 14" hubcap, (only one?) your wheel is a 15". The cap is a full wheel cover, note the hole for the valve stem. If you could get a measurement from your wheel, from inside the shoulder to inside the opposite shoulder across the center and get one from the hub cap lock ring and see if they match.....or just buy it, restore it and use it to serve adult beverages at the campground.
BTW...I always liked the way the full stainless moons looked on our 63 Safari.
"Sticks & stones can break your bones...and hail will dent your Airstream"
So when is this..."old enough to know better" supposed to kick in?