The sometimes successful trick to this is to find the Ford part number. You can do that by going to the various places that sell OEM parts for a discount, searching for what you need, then searching the part number on Google. Do a search for "Ford OEM parts online." If you find something that looks like a positive result, double check. I came up with two part numbers that were labeled as main bearing cap bolts. It's quite obvious one of those results are cylinder head bolts. The other result is D4FZ-6345-A. There are several results on eBay and other places, but I didn't see any pictures to confirm they are the correct bolts. Also look at the companies that sell engine parts and gasket sets. I took a look at Federal Mogul (Sealed Power and Fel-Pro), but didn't see them there. It doesn't hurt to try the local engine rebuilders and machine shops to see if they can order a set for you. The last option would be the companies that sell performance parts. They use upgraded fasteners, but it's probably going to be expensive. The last option would be to walk around a boneyard with an impact wrench. The local pick n pulls here will not sell fasteners unless you buy something else that they go into, but they will add a dollar per bolt.