Neither Lowes' nor Home Depot's websites list "Euro Screws". But since both stores are within 3 miles of my house, I went to Lowes.

The manager of Lowes' hardware department said they don't carry "Euro Screws" and he said they had no other "fasteners" that would work for my situation (i.e., the fasteners being attached to the underside of a particle-board desktop that would resist the downward force from the slide-out keyboard shelf on brackets below the desk top).

I then found EZ-Lok threaded inserts on Amazon for $5.00 and added that item to another item I ordered two days earlier so the shipping was FREE for both items.