SB, try contacting OP. They may be able to send or sell you the machine screws.
Otherwise, pick up some 1/4" or 5/16" machine screws so the heads will "sit" properly in the recessed holes in the spacers.
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"Whether active duty, retired, national guard or reserve - is someone who, at one point in their life, wrote a blank check made payable to "The United States of America", for an amount of "up to and including my life". That is HONOR, and there are way too many people in this country who no longer understand it." -Author Unknown