I have no idea how it worked with Pewexes, it's not my times, but I have heard that there existed also something like "dollar coupons", "bony dolarowe". Was it so that it could replace dollars while shopping in
Pewex, since it was somehow illegal to possess dollars in Poland? But on the other hand, if it was so, what was the sense of the "cinkciarz" profession, if the dollars bought from them were illegal?
In the times of Warszawa and Syrena, very small number of people possessed cars. In my town, the current population - below 15 thousand citizens (and decreasing), I have no idea, how it was in the 1950's and 1960's (I believe that less, but increasing - maybe 10 thousand?), only a few people in the whole town had cars. The first car that was available to everyone was Fiat 126p, commonly known as "Maluch" or "Mały Fiat" (Small Fiat), as opposed to the Fiat 125p, known as "Duży Fiat" (Big Fiat). Although it was anyway expensive and you needed to wait many years after ordering it since the factories weren't efficient enough to satisfy the demand. However, the real car boom happened in Poland only after 1989, when cheap second-hand cars started to be imported to Poland.
What I remember is that in 2005 Fiat 126p "Maluch" was still the most commonly met car on Polish roads. Maluchs were then definitely less than 50% of the cars in Poland, but they were still most popular.
Before 1989 there were imported cars in Poland, but they were from the other Eastern Block countries - like: Trabant, Wartburg (East Germany), Łada (Soviet Union), Skoda (Czechoslovakia), Dacia (Romania).