Fair comment, Phil, but I can't see why - if these were destined for the US anyway - they would have made them with the Dutch cat#.
There are other 'Portrait Of...' discs on Discogs which are on Columbia with the '5C-' cat#s. None of them shows any US issues, so it's impossible to judge from that.
On top of which, would there have been enough of a call for Gilbert Bécaud 'product' in the US to justify issuing this in the first place, let alone schlepping it across the Atlantic?
Could this have been made in Holland especially for the USA? I see that the linked Netherlands release is on the Columbia label, which Capitol/EMI wouldn't have been able to use in the States because CBS owned that name. This has a parallel with UK Decca and later PolyGram making LPs in England and Holland on the London label for US and Canadian release.