...good opening for a 3rd party solution if there's not one out there already. It wouldn't be pretty, but there'd be a market for it.
This Amazon
page shows a half-zillion third-party solutions, many not pretty, but… .
Not all
that many, because the selection pretty much peters out at the top of page 2, but thanks for the link; I'd add a locking solution to my list of items lost to miniaturization, but my edit time period has expired, so...
Replacement for Kensington lock slot: looks like $50-75 for a solution that's obtrusive at best.
If I'm in the neighborhood, I'll pop into the Apple store and see what their solution is; my guess is that they'll revert to Airs and better security as opposed to using a totally 3rd party solution.