GeoJeep33

As stated in Planman's write up, and as mentioned by others, the manufacturer used "off-size" bolts for the track bar. I believe it has been mentioned to maybe swith to the proe bolt size of 9/16", is this correct? Grade 8, or something to that effect?

If so, and this is the real stupid question, can I pick those at any auto parts store, or are they special order?

Thanks in advance