In the Ford CMP parts manuals the solenoid is listed as 01A-11450 A.
Macs Antique Auto parts has them listed as 01A-11450 (Steel case solenoid with starter button). Works on 6v positive earth. 21A-11450 is listed as a Bakelite case without button, but cheaper. We get the steel case solenoids here regularly at swap meets fairly cheaply, but they're Chinese or Indian made and last a matter of months before dying.
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