Grade of screws and bolts

I need a couple of screws/bolts for my carbs and dont know what grades are good for the job. Will hardware stores carry this stuff? Or is there a good place online? I only need a few. I did a search and came up with zilch.
I need the adjusting set-screw (M5 .80 25) for the top lever on the carb. And the corresponding lock bolt (M4 .70 I think)
I may just have to get a screw with a head on it (and do some cutting) to replace the set-screw. They don't seem to come that long.

that should just be grade 2 hardware you need hardware store might have,or theres always my heroes at fastenal;)

Thanks wireman