How old is this Greek bouzouki?

[The Ferryman]

Is there anyone out there that can help me to find out the age of this 8-string bouzouki?
It came into my possession in 1970, 49 years ago.
At that time it was already well-travelled and weather-beaten and I don't know for how long it had been in the previous owner's possession.
I am at least the third owner, possibly the fourth.
When it came into my possession it had received a vicious blow from its previous owner who was intent on its total destruction. (don't ask me why)
It was cracked from the top of the arm to almost all the headstock.
I am sure it must be a good quality instrument because in spite of the damage the instrument didn't collapse. Surely a lesser instrument would have collapsed under the strain.
After a lot of time and loving care I restored it to the beautiful instrument you see in the photos. It's been in my care for the last 49 years.
It doesn't play as sweetly as my main bouzouki, but the joy of playing a renovated instrument is something to be treasured.
It's not for sale, but I'm curious as hell to know how old it is.
I'll give some details to help any experts out there.
In spite of its age, and the abuse it received, there is no sign of any warping at all!
The headstock and arm are one piece. When I re-varnished the entire instrument I put black varnish on the headstock to disguise the 'scar' left by the break.
So originally the headstock and the arm were the same wood colour.
The tuning machine in the photo is no longer there. After it ceased to work I replaced it with a Grover tuning machine.
It has 21 douyes, there is no label inside and no truss-rod.
The inside of the bowl seems to be lined with dark green paper.
It has 26 frets (excluding the 1st fret next to the nut/bone ).
The top note on the 'D' string plays 'E'.
On a modern bouzouki the top note on the 'D' string plays 'F'.
The overall length is 98.5 cm.
The width of the body is 27 cm.
The depth of the body is 18 cm.
If there is anyone out there who can give me an indication as to its age I would greatly appreciate it.
If anyone needs more measurements or photos I'll gladly supply them.
...Thank you.