You can still cherry pick slabbed 1973 coins in MS-65 but it will probably cost 20 or $30 if you find one.
I believe this coin is overgraded. I'd call it a nice gemmy MS-64. Almost 3% of '73 Ikes are nicer than this. It looks like it even has a little mint set hazing on it meaning it wouldn't wholesale for $4 as a chBU.
https://www.ebay.com/itm/1973-EISEN...644768?hash=item2f5487bce0:g:4GIAAOSw2QlgLTnL This one looks scared.
it is not much different than this https://www.ebay.com/itm/1973-Eisen...asedWebDarwoV3&_trksid=p2047675.c101195.m1851
1973 Philly planchets were plagued by tiny flaws which did not strike out. Because these coins can be found only in mint sets which we intuitively expect to be of very high quality, I think the challenge in finding an appealing example was completely unexpected.
There are undergraded coins out there. Some graders grade everything pretty high and a nice example could have been graded. Finding them might be even harder than finding 2000 original '73 sets without tarnish.