Ok guilty on all charges your honour...
I came from there... meaning I lived in Italy from birth (1961) to 1985 then came over to UK when the company I work for, asked me if I wanted to...
The first band I joined, I didn't even have a bass, so the manager bought me that Eko right there, same colour same everything, second hand and the strings I estimate them to be at least 6 or 7 years old, almost brown and the roundwond wrap worn to a quasi flats state. The one I had I am sure it didn't have that thumb rest though. Someone added that.
Yet it was light and fragile and any attempt to turn the trussrod to reduce the action gave a nasty result of strings buzzing at different parts of the neck, highlighting a very badly warped neck that no plek in this world could fix.
Now it sounded better than it played but you could wedge a quarterpounder with cheese between the strings and the fingerboard. On the plus side it had a very thumpy bass sound and the strings were never changed from the day I was given to the day I left the band to move over to UK and I gladly gave it back to them. But hey we recorded a lot of popular hits with that sh|tty bass, and people who were listenting to the records would ask me, what kind of effects I used to achieve that thump, when all it was, was a jack cord straight into a 24 tracks input not even an amp. We were very poor, I always played that bass through a pa, I never owned a proper bass amp until much later.
The date in which these were produced I read, according to Chitarre (an italian magazine) to be between 1979 and 1983 when they were discontinued.
Rest in peace and never come back, is what Id say