the hardware store has bolts for way less then summit. they sell grade 8 bolts, they never break. well almost. grade 8 will cost the most, at 50 cents a bolt, 25 cents a nut. 6 cents a washer, see where im going with this? lol

if you have to drill them out, just bring the drill it into the store and get one thats that size, or read the bit for its size, either way your looking at a couple bucks worth of nuts and bolts should it come down to it.