I found graphics for the sign itself on the Internet, including the smaller additional sign with a dummy company name and telephone number. I substituted those for the real name and number using MS Paint and Power Point. I printed the sign on ordinary printing painter and glued it to a piece of styrene.
The post is a length of 2 mm brass tubing.
I tried to model the back of the sign as well, with the appropriate hardware that fixes the sign to the post.
Painting of the post and the back of the sign remains to be done.
Yesterday I also received the 3D printed tree grate and storm drain. Here they are, as received.