D140 in the 60s,then K140, and E140, but I'm not sure of the order or time of the last two.
I had one of the Kustom 200 and 2x15 D140 cabs back in '65-'66. It really needed two cabs to increase the volume for some gigs.
Ended up going with a Sunn 2000s/2x15 Sunn D140 cab. Sunn cab moved more air and seemed to be more efficient.
Both sounded great! First with '63 Hofner and then '64 Fender Jazz.

