Up for Buy-It-Now are 8 new old stock valve tappets, GM part number 5231880.  According to my GM Manual, these are used on the following models and years:

1956-1959 Chevrolet Truck...Series 3 (6 cylinder)
1960-1962 Chevrolet Truck...Series 10 thru 30 (6 cylinder)
1960-1961 Chevrolet Truck Fleetmaster (6 cylinder) (Except Powerglide)
1963 Chevrolet Truck...4/WD (6 cylinder), (1st Series)

  The manual indicates these are :mechanical type, (2 3/16" long-two piece body)". The tappets are in brand new, never used condition and are free of any rust or damage.  The box indicates there were original 12 in the box, however only 8 are left.  The original box is dusty from many years of shelf storage.
  Please feel free to E-mail me questions.  International bidders are always welcome.  Thanks for looking!!!