No. "Park vacancy" would refer to "oferta", so the "expression" would be used along with others, like "park vacancy offer/raise/rate'' etc, to give meaning to it.
Let´s say, "a taxa de oferta de vagas de garagem" - Park vacancy rate, and others.
e.g.
Trevor Wood - General - UK, Retail park vacancy rate at worst level since 2008.Reino Unido, ritmo de vagas no/à varejo está no pior nível desde 2008.
http://www.propertymall.com/property-ne ... since-2008------------------
Job vacancy - oferta de empregos.