They can be on the expensive side if there is local resources. In my case not even 1/4 mile away is an industrial hardware store and they had the flat head versions which were entirely adequate.

Granger is another company that sells similar stuff.

There is also a local company Fastenal. https://www.fastenal.com/?gclid=EAIaIQobChMIlOHg44m17QIV0ACtBh1XLwLfEAAYASAAEgIG6PD_BwE

I was looking at there site recently as I may have some upcoming project. They are more then a dollar less each for the bolts I am looking for then the local industrial hardware and their Store is also local.

__________________
84 300D, 82 Volvo 244Gl Diesel

I have done this with duct tape and a drop of oil off the dipstick. Works great. My problem at that point is knowing how far in or out to put it. Also knowing how to level it. Getting the front of the hole to match the pin is the easy part.