In the Catseye -verse a constant favorite of the Nakano family is the Keiju style of Japanese movies. because they are constantly talking about them and watch them almost every family gathering, I decided to oput the ones I could find here. These are really all giant monsters, not just Godzilla. and it includes some of the Ultraman as well.(different studios).

Big G movies (Godzilla)
https://archive.org/details/BigGMovies
Individual Movies
Godzilla Raids Again (1955)
https://archive.org/details/3.godzillaraidsagain1955engdub
King Kong vs Godzilla (1963)
https://archive.org/details/KingKongVs.Godzilla
Ghidrah, the three-headed monster (1964)
https://archive.org/details/GhidrahTheThreeHeadedMonster
Gamera the Invincible (1966)
https://archive.org/details/gammera
Godzilla vs The Sea Monster (1966)
https://archive.org/details/GodzillaVs.TheSeaMonster
Son of Godzilla(1967)
https://archive.org/details/SonOfGodzilla
Godzilla vs Gigan (1972)
https://archive.org/details/GodzillaVsGigan
Godzilla Vs Megalon (1973)
https://archive.org/details/GodzillaVs.Megalon
Godzilla Vs Mechagodzilla (1974)
https://archive.org/details/godzilla-vs-mechagodzilla-english-dub
Terror of Mechagodzilla (1975)
https://archive.org/details/TerrorOfMechagodzilla
Godzilla Cartoon series (1978)
https://archive.org/details/05.-the-seaweed-monster
Return of Godzilla (1984)
https://archive.org/details/ROGEOST
Godzilla 1985
https://archive.org/details/Godzilla1985RedMenace
Godzilla Vs Ghidorah (1991)
https://archive.org/details/GodzillaVs.KingGhidorah
Godzilla vs Destroyah (1995)
https://archive.org/details/12619-1-1533670176.mp-4
Godzilla the animated series 1998)
https://archive.org/details/godzilla-the-series-ai-upscaled
Godzilla Against Mechagodzilla (2002)
https://archive.org/details/GodzillaAgainstMechagodzilla_201703
Godzilla Vs The Smog Monster. (2008)
https://archive.org/details/GodzillaVs.TheSmogMonster
Shin Godzilla 2016
https://archive.org/details/ShinGodzilla_201811
Godzilla Monster Planet trilogy
Monster Planet (2017)
Godzilla City on the Edge of Battle (2018)
Godzilla the Planet Eater (2018)
https://archive.org/details/49.-godzilla-city-on-the-edge-of-battle-2018
Destroy All Planets (1968 Japanese monster movie)
https://archive.org/details/Destroy_All_Planets
The war of the gargantuas (1970)
https://archive.org/details/TheWarOfTheGargantuas
Rebirth of Mothra (1996)
https://archive.org/details/RebirthOfMothra
Ultraman (1966 English dub)
https://archive.org/details/ultramanepisode13englishdub
Ultraman 1966
https://archive.org/details/ultraman-1966