James;
Go to a Napa outlet and have them look it up in their Echlin-United book.
That 6V starter relay is a pretty generic part that Chrysler used on a lot
of their cars and which Autolite undoubtedly made for other brands, there
should be an equivalent available. Once you have the number any auto parts
store can cross reference it if you don't like Napa's price.
Best Regards
Arran Foster
1954 Imperial Newport
Needing A Left Side Tailight bezel and other trim parts.