The two closest "modern" pedals to the speed king would be Tama's King Beat from the late 70's/80's and the Trick Pro 1V pedal. A close third would be Slingerland's version of the speed king. There have been other direct drive pedals with a standard spring before and currently. Yamaha is the biggest proponent of offering direct drive, as is Pearl with the Demon, Slingerland had the yellowjacket, premier the 252.....direct drive alone does not make a speed king....compression springs would be a more accurate comparison, like the first two I mentioned.....
Whats the point of this again? :p