There used to be a German paper model site that had an assortment of very good hand drawn paper models of old locomotives, trucks and buildings, ect, that could be downloaded. It is no longer an active site, and I don't remember its name so I cannot look for it in the Wayback Machine. This is very vague, but someone here might remember the site and see if it has been archived. One of its models was similar to the featured above.
UPDATE
The site I was thinking of was
www.bastelbogen-online.de
One of the models from that site can be found here
http://www.kdtroeger.de/c8.htm
Bastelbogen-online is no longer an active site, and it was not saved by the Internet Archive.
All those models will be lost in time, like tears in rain.