American Flyer Standard Gauge Engine screw

[JonEddy]

I was able to take the other screw off the fire box and find a match in size at the hardware store. It's a 6-32 x 3/4" screw btw.

[JonEddy]

Can anyone tell me what would be a good replacement for the fire box screw on my engine? Yes I have a screw loose ! One of them must have come loose over the past 25 years and I can't find it anywhere. Thanks in advance!