I only collect 1960s Killebrew memorabilia, and while the image used for these postcards is from the early '60s, is there any way to know if the postcards are of the same vintage?

I've read that it's easy to tell under magnification if an RPPC is "vintage", but does that necessarily mean it's the same vintage as its picture? And can I make any judgment based on eBay scans? Does the back of the "full bleed" one narrow the years down much? How about the copy with the thick borders? Does that likely pre-date the full-bleed one? The seller of the thick-bordered card lists it as an original Brace postcard, but I don't understand how that's determined, or if that even necessarily dates the item to the 1960s.

Thanks in advance for any tips or advice!