What pattern of position lights did early Soviet jetliners use?
That was a tough one. The USSR joined ICAO in 1970.[a] The colors and positions would have been the same, since those carried over from maritime conventions.
What isn't the same, based on checking warbirds, is the viewing angle. The red/green lights in ICAO/Western standards are not viewable from behind, but Soviet aircraft did not have that distinction. They also had separate top/bottom navigation lights, even the license-built DC-3 (Li-2) was modified to have that top/bottom arrangement.[1]
Judging by the Yak-40 (an early Soviet jetliner), they lacked the white wingtip lights[b] that are viewable from behind -- compare with the ICAO-compliant Il-62 (shown on the right):


Both aircraft are stored; sources: scalemodels.ru and elevation.maplogs.com

For the aforementioned warbirds, below shows an American F4F (annotated) and a Soviet Il-2:


Sources: primeportal.net and primeportal.net


1: http://www.dc3history.org/airlinesoftheworld/russianaviation.html
a: I'm not sure whether Soviet transport aircraft that flew internationally and were built prior would have been retrofitted
b: technically those are anti-collision lights, but unfortunately the Wikipedia statement is vague and lacking in-line citation -- the ICAO-equivalent became effective in 1962 according to SARPs Annex 6 part 1