Here's my Christmas gift to you all, the original Japanese versions of the original Showa era Godzilla films in glorious high-definition, in Japanese with English subtitles FOR FREE! I ripped these from the Toho Blu-rays, sans Godzilla '54 (ripped from the Criterion BD), Godzilla vs. Megalon (ripped from the Tokyo Shock BD), The Return of Godzilla (ripped from the Kraken BD), and Godzilla vs. Biollante (ripped from the Echo Bridge BD).
You'll notice I added The Return of Godzilla. While the film is the start of the Heisei series, it was still produced during the Showa period in Japan. So it's technically a Showa era film. Have a Showa Godzilla marathon before the release of Legendary's GODZILLA: KING OF THE MONSTERS (2019) and GODZILLA VS. KONG (2020).
You can directly stream or download the films from Internet Archive, here's the list:
GODZILLA (1954)
GODZILLA RAIDS AGAIN (1955)
KING KONG VS. GODZILLA (1962)
https://archive.org/details/king-kong-vs.-godzilla-1962-japanese-version-criterion-collection-bdrip
MOTHRA VS. GODZILLA (1964)
https://archive.org/details/mothra-vs.-godzilla-japanese-version-criterion-collection
MOTHRA VS. GODZILLA (1964)
https://archive.org/details/mothra-vs.-godzilla-japanese-version-criterion-collection
GHIDORAH, THE THREE-HEADED MONSTER (1964)
https://archive.org/details/ghidorah-the-three-headed-monster-japanese-version-criterion
INVASION OF ASTRO-MONSTER (1965)
https://archive.org/details/invasion-of-astro-monster-japanese-version-criterion
EBIRAH, HORROR OF THE DEEP (1966)
https://archive.org/details/ebirah-horror-of-the-deep-japanese-version-criterion
DESTROY ALL MONSTERS (1968)
https://archive.org/details/destroy-all-monsters-1968
ALL MONSTERS ATTACK (1969)
https://archive.org/details/all-monsters-attack-japanese-version-criterion
GODZILLA VS. HEDORAH (1971)
https://archive.org/details/godzilla-vs.-hedorah-japanese-version-criterion
GODZILLA VS. GIGAN (1972)
https://archive.org/details/godzilla-vs.-gigan-1972-japanese-version-criterion-collection-bdrip
GODZILLA VS. MEGALON (1973)
https://archive.org/details/godzilla-vs-megalon-1973-japanese-version-criterion-collection-bdrip
GODZILLA VS. MECHAGODZILLA (1974)
https://archive.org/details/godzilla-vs-mechagodzilla-criterion-rip
TERROR OF MECHAGODZILLA (1975)