I don't know the years, but I'd venture to say that it was either uprights or electrics with flats for the originals of theirs.
A lot of TB rates D'addario Chrome flatwounds pretty highly. I Use them in a seven piece Band I play with

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labella's seem to be a more traditional sounding flat (as Im told, Never used them)
My vote goes to either Flats, or Tape wounds.
Preference in Tension, cost and brightness matter. Let us know what you've been using and it gives a better starting point for comparisons