Hi Patric,
Since this boats have been built in years 1967 up to 1973 I doubt you can get the CE conformity certificate. You may consider, as EU resident, to register your boat under the Polish flag, still EU, less formalities and no obligatory technical inspection or renewals.
I have recently registered my new build by myself boat, as well as helped to register boats for my two Portuguese and one Hungarian sailors. If interested contact me at kris@kmatuszewski.eu . This will take about a months, since the Polish sworn translation documents is necessary. First you will get the electronic temporary certificate, then the hard plastic copy will be issued.