Wave,
Can you define what a bunch is? 10, 100, 1000?
The problem is that socket manufacturers and resellers don't list the outside diameter of the socket, so it's anybody's guess one what the actual outside is until you measure it.
The sheet metal style ones you're thinking of are typically for very large nuts, commonly for water heater element removal. Just google water heater element socket.
How much torque are you applying to the fastener?
Do you have any opportunity to change to an Allen socket head fastener? That would easily fit down in that hole, and Allen driver tools are readily available. Here's an example of that type of fastener:
https://www.mscdirect.com/product/details/05520077

Depending on your quantity needed, if it was less than 100, I'd take Marv's suggestion, and turn an existing socket down on the lathe. A machine shop could knock those out in short order. If you needed less than 10, and don't have a lathe, then the angle grinder method would work just fine.