Here is a vintage catalog listing for a rubber stamp outfit. The set contained letters, figures, signs, inking pad, bottle of ink, guide strip and spacer. The price for the kit was $1.50 for letters 7/8” high and $3.50 for letters 1 1/2” high. The ad is is from the Northern School Supply Company Catalog, published in 1913. 

Here is a black and white clipart version of the stamp outfit from the ad.

Click on images to enlarge.