can anyone identify a pair of 73mm pistons (2.86" and 2.87") shallow dish, valve pockets and stamped 24 282 LH A and 242 83 RH B. at the moment they reside in a 750 dunstall cylinder affixed to a 72 commando. atlas??? early commando? also a cylinder head with number 06-0380 cast into bottom of bottom fin and "C" stamped top center between valve covers. combat head i assume but i can't find 06-0380 in any of my parts books? thank-you, b