Here's a lovely star finder wheel made by C.S. Hammond & Co around 1950 (the date of the copyright). I like that someone actually used this thing, as evidenced by the repairs made with cellophane tape. This measures ten inches and, in real life, is a bit more on the turquoise side than in these photos.
Check out the reverse side. It's chock full of information for the budding astronomer. My favorite part is the instructions and the use of the word "thereon" therein.