It seems you are right about the „Volendam“.
I just had this card of a Mennonite refugee with the same details of departure (date, destination…)
more details about the Volendam and her meaning as for Mennonite emigrants:
As for the date of departure: I read 6 oct. 1948 (in „my“ card). Also see Mrs Feldmanis’ date of arrival: 02.10.1948
Maybe this is her in the passenger list of the „Volendam“, arriving in Argentina on 28.10.1948:
FELDMANIS- SZARMANS, Elizabete, 42 y (in 1948)
next to her name: FELDMANIS, Alksejs (12 y), maybe her daughter/ relative? the name crossed out in this card?
Enjoy your weekend!