But lo and behold, here it is: the original 1957 EP of 'Skibet sjal sejle i nat', with four tracks by Birthe Wilke with different duet partners. The cover may show some wear, but that is no surprise after 65 years. It's just a pleasure to own one of those early Eurovision singles.
My collection: 7" single no. 6846
Found: Discogs.com, received 24 January 2023
Tracks: 'Skibet skal sejle i nat' (Birthe Wilke & Gustav Winckler), 'Tre piger fra Jylland' (Birthe Wilke & Dirch Passer) / ''Militaer tango' (Birthe Wilke), 'Kaerlighedens cocktail' (Birthe Wilke & Gustav Winckler)