Vintage Navy with White Belted Dress

Brand tag is missing, but this came from a lady who owned some great brands! Dress is 50s or 60s, fabric is poly or blend. Has one string belt loop, on left side, not sure if one is missing or was just never there. Matching thin belt is included. Elastic finish on sleeves, buttons up top with 4 original buttons. Super sweet dress. Size is approximate, XS to S.