sammy; if you have a late model (fill in your profile please);
5 - 8x70mm 1.5 Pitch Metric Bolts
or
12 - 8x45mm 1.5 Pitch Metric Bolts
info courtesy of froggman at
http://www.froggmann.com/Tech/Topremoval.htm
depends on which bolts you stripped..
try Ace or NAPA
good luck!