@jrp I had the same thought that it could be an answering machine. Someone handles 8-tracks earlier in the movie though. Maybe it's a Japan-only device and I should try a search in Japanese.
I doubt it's a show model. The director is not exactly known for his high-budget productions. Plus the device is clearly branded Pioneer. Maybe a prototype?

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@settima Sold as Dictophone Ansofone 650 in the US
https://www.radiomuseum.org/r/dictaphone_ansaphone_650.html
That one is the Pioneer branded Japanese version early 70s.
CoolTech
https://www.tokopedia.com/alvinmo-leather/tape-pioneer-ansafone-vintage-rare
Pioneer lists it on their archives Under other businesses
That was fun but now I have a sudden desire for the AF810
https://global.pioneer/en/corp/info/history/chronology/archives/1968/
@settima Well yeah I guess that checks out then,