So its Czech (velikost is size in Czech and Cena is price in Czech)...That puts a whole different spin on it. It could be 1986.
Even though I don't feel it looks anything remotely like early 60s, researching the VKV Vamberecka drajka, Vamberk, I found the blurb below. Mind you, it's all about lace and this dress doesn't have any. Very curious to find out the date, Melanie!
DING DING DING we have a winner... Well done, perhaps you have another Guess the Year for us? and here is the evidence. I must say it surprised me when I saw the date, as even the tag doesn't look that new. It's still on string for goodness sake! and no care labels either...so apparently the 1970 material content laws did not apply to eastern Europe (Czechoslovakia still being communist at this point).