All you need is a # 10 x 32 tpi screw that is 2" long. They can be bought at Home Hardware or Home Depot.
I once ordered some of the fiberglass stock screws (upper) from Numrich for $ 4.00 each. I ended up recieving a few of the Home Depot style replacements. That was after paying about $ 5.00 USD shipping. Was I ever pisstov.
Thankfully with the cheaper Home Depot screw and bolt, nobody will see that cheaper fix. Save your money.
Cheers,
Barney