The Chaika, a slavish (literally) imitation of a mid 50s Packard, was used for middle level Soviet officials.

Report from Cuba:

"What keeps the big American cars going?" I asked. I couldn't quite see second-hand Lada engines hitting the spot.

"Russian parts" the driver replied. "From trucks. They fit the American engines."

It turned out that after the war the Soviets found it easier to copy American products than to design their own. Unfortunately they forgot the bit about updating them every four years or so. '49 Chevy look-a-like trucks still trundle across the Steppes. The Soviets also copied the huge V8 petrol engines which then powered American trucks as well as cars. As a result blocks, big ends, pistons and rods from obsolete Russian trucks keep antique American cars on the road in Cuba.