Possibly trimmed cards - thoughts?

[ASF123]

I recently received 4 cards from the same eBay seller - 71T Aaron, Bench and Kaline, and 72T Clemente. They are all in generally great condition.

The issue is that the Clemente and the Bench look almost 1/16 inch too narrow, and the Kaline and Aaron may also be a little narrow (?), although less than the other two.

I looked at the edges with a 10x magnifier, and they did look quite smooth compared to others of the same years under magnification. But I have no experience in that area, and it could be that they just have nicer edges.

I contacted the seller - he is willing to accept the return but says they came from factory sets he received back then and he "hasn't looked at them since 1980." He also says he measured other cards from the sets and they are 2.5x3.5.

I have no reason not to believe him, but of course no reason to believe him either other than that in negotiating the sale (this was outside of the auction) he was communicative and nothing seemed shady whatsoever. Seller has only been on eBay for about 6 weeks, but 20 positive feedback and no negative. He has a decent inventory of late 60s/early 70s cards for sale, including other 71Ts that could plausibly be from the same factory set.

Thoughts? Could factory sets from that era have included cards that were cut a bit narrow?

Thanks in advance for any advice.