While the plaster took an hour or so to set up hard, we needed some source material.
I grabbed a neckerchief because it had a nice embroidered logo I could scan.

I grabbed some nearby stuff to weigh it down flat on the glass and scan it.

Then I opened the file in GIMP and trimmed away the extra stuff. Resized it too so it would fit the hockey puck.

And printed it out. Here is a sheet next to a plaster puck.