That drum only came in 5 or 6.5x14 not 5.5.I highly doubt that it's a 60's brass keystone badge,but more likely an 80's or newer,large aluminum Chicago or Monroe badge drums.Ludwig only made ludalloy or brass supras in the 60's,and the COB serial numbered drums,are rare.If it's a bronze supra,with a small brass serial numberd badge,then it's possibly prototype,and rare indeed.Ludwig didn't introduce bronze supras till the early 80's.Pics will help.
Steve B