I just ordered them from McMaster-Carr, you can buy as few or as many as you like. I'd say you are looking at $25-40 to fix that, yourself. You will need to buy a tap and drill for the next size up to install, as well.

"Regarding anti-seize: it seems that I ran across this at some point. I've heard that it will interfere with torque value. Any knowledge on that?"

Common sense says a lug with proper anti-seize on it is going to torque a lot more accurately than a dry bolt in a dry hole that galls before it reaches full grip. If you ahev ever had a stainless nut gall on a stainless bolt while running it down with your fingers, this will be very clear. I have been using anti-seize on all my wheel studs adn bolts for several years now and have never had one loosen up or fall off... or gall and strip.

"FSM torque values for wheel bolts are dry values for clean, rust-free threads. If you lubricate the bolt and use the same torque value, you will be applying more clamping force. That risks damage to rims, bolts and threads. The bolts are probably 25% below their load limit at specified torque, so you may have enough reserve strength to get away with it. But it's a still a risk you need to think about. If you know the thread size, you may be able to find a table of appropriate wet torque values by internet search."

The amount of extra force applied with the anti-seize is going to be negligible, percentage wise, if in doubt, torque to the lower value of spec and it would not exceed the upper limit by more than single digits percentage in the worst case. The torque wrench could be that far off unless you have it calibrated yearly. A lot less likely to damage anything than galling, as is the case with the original issue here.

And no, don't anti-seize the tapered seat of the wheel or lug.