I suspect fake, perhaps copied from one produced in an early 1960s experiment by David Sellwood, dealing with speculated Greek minting techniques. Looks very similar, but the bottom edge here - what we can see of it - suggests the two halves may have been produced separately.
Neat gift idea, though. I hope my nephew, who is pursuing a grad degree at MSU, doesn't get wind of it. Otherwise, I might have to get him something similar.
Most ancient coins with crested Corinthian helmets depict those helmets being worn by Athena or others. It's not impossible to find legit coins with empty helmets, but they are often on very small denominations (as in, you might need a magnifying glass to see the imagery), or the helmets they show may not be crested. Or the helmets may be similar, but not identical, in shape to the MSU version. Or they may be cost-prohibitive. Lots of challenges.
Not sure if the following links will all work...
If you'd like to bid more than $20,000:https://www.sixbid.com/en/the-new-y...ttium-temesa
Another which will no doubt go for a high amount by the time the dust settles:https://auctions.cNGCoins.com/lots/...5mm-251-g-5h
Here are others, more affordable perhaps, but tiny:https://www.romanumismatics.com/234...w=lot_detailhttps://www.vcoins.com/en/stores/lo...Default.aspx
Slightly different helmet type here, and also tiny:https://www.vcoins.com/en/stores/gb...Default.aspx
Tiny, not crested:https://www.vcoins.com/en/stores/sh...Default.aspx
Larger here (though still small), but not crested:https://www.vcoins.com/en/stores/ma...Default.aspxhttps://www.vcoins.com/en/stores/ma...Default.aspx