Replacement Screws for Atlantic Pools Concorde Gibraltar 18 x 33

Hi,

Can anyone tell me what the part number (or screw size) is for item # 3 in the linked diagram is?  My screws on my top plate have started to complete corrode away and am looking to get teh exact replacements.  Thanks!

http://www.inyopools.com/parts_concorde_18_x33_oval_52_wall_steel_top_rail_steel_upright_.aspx