Header bolts size

[desertdogg]

Ok one of the 100 little things I need to do is find some header bolts as I lost the manifold bolts when they were taken off and for some reason I cant seem to find them or at least decently priced ones. I have found some online but they dont say the size or thread pattern, I know they are metric Im thinking M8x1 or 1.25 does anyone know the size I need for my 07 5.3 ? and where to go to get some ? I went to the local Home Depot but all they had was SAE grade 8 not in metric tho...I refuse to pay the 30-60 bucks that these places i found want. they are just freaken bolts, somewhere there has to be a place I can go to find these at a reasonable price... thanks for any help oh and I am going with some shorty headers if that makes a difference