Here's a couple for your list:
1 pop
Genco, Rocket, 1950
Fashion Show, Gottlieb, 1962 (only one bumper is a pop bumper thats energized, other bumpers just score points with no reaction)
Jungle, Gottlieb, 1972
Countdown, Gottlieb, 1979
Hollywood Heat, Gottlieb, 1986
Total Nuclear Annihilation, Spooky Pinball, 2017
2 pops
King Pin, Gottlieb, 1973
Champ, Bally, 1974
Top Score, Gottlieb, 1975
Spin Out, Gottlieb, 1975
Zankor, Zaccaria, 1986
Scramble, Tecnoplay, 1987