Welcome Pixie...
The smallest minature transmission chain & pinions is I believe from the American SPD-SI Group......however is 1.87mm pitch, not 1.5mm pitch
http://www.sdp-si.com/contact/quote.phpI find them excellent people to deal with, however you may need a second mortgage on your home
My application is an actual drive, I would not consider their product for for any static model
The winch you show could be driven by an AC motor and speed reducer or a DC/MG set with speed control.......it is also possible that the actual speed reducer is mounted and fully located within the bore of the main drum, hence...may not be visible to the naked eye
The [aft] chain driving downwards would appear to be for the
double helix horizontal pay-in/pay-out screw shaft for correct layering of the main wire. Not sure what the other chain function [in the fwd direction] could be.......
So the function of the double helix is simple, a nut with an internal double female helix is the carrier for the wire feeder roller hub......so when paying in, the direction of rotation of the main drum is constant, the small roller chain drive from the main drum doesn't change direction, however as the nut reaches the end of the horizontal displacement, it re-engages in the opposite direction helix thread and progresses until the opposite movement re-engages again etc...all without changing any direction of shaft rotation
From this, a 1.5mm pitch chain may be for a
1:10 scale model?.......or a ~~15mm pitch chain drive in real life....
Hagglunds Marathon hydraulic drives for Naviere Stern Ramps had a similar winch wire drum sizing you have displayed. These used a 5/8" [~~16mm pitch] duplex roller chain for the winch rope carrier
So I must ask, what scale do you propose?
regards Derek
PS......Google suggests the following for the Smit Rusland .......they may be able to offer more information......
Towing winch Van der Giesen, IHC DMN, maximum pull 163 kN on third layer