Barry:

 

I don't know where you live, but down here in South Texas we have a company named FASTENAL, and all they sell is screws, nuts &bolts, etc.  I once had a scroll saw that took a screw with a special head that the vendor charged me 60 cents each for.  I bought a whole box of the same fastener with a hex head from Fastenal for 8 bucks!  You may not want a whole box, but it will save you money and frustration in the long run.

 

Arnie