The fuel pump bolts are 5/16"-18, plain old standard-thread grade 5 bolts. Any hardware store or home improvement center should have all sorts of lengths of them in stock. Just take your pump in to the store, and find a bolt that will allow about 1/2" of thread or a little more to stick uot the back of the mounting flange. It's also a good idea to use split-type lockwashers between the bolt head and the pump housing. Just be careful that the bolts don't stick through the block far enough to be hit by the camshaft as it rotates.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!