If anyone can get you the size (I don't know it offhand - but someone here might,) check to see if ARP has a kit in that size (there are six, as I recall,) or get a good set of SAE Grade 8 bolts (or socket head capscrews, which have smaller heads and are usually at or near Grade 8 specs.)
Another good source for high-strength bolts is a tractor parts dealership - I used to get REALLY good hardware at Quality Farm & Fleet back home - and I wish they were out here!
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