This Ben Kraft FDC was just discovered on Ebay. Ben Kraft is known for making handpainted add-ons on US FDCs. His covers spans from 1940 – 1980s and he often had a humorous touch to his paintings. Some of them are still possible to obtain for affordable prices, others are quite rare and expensive. The SA cover is quite rare and has a picture of Mickey Mouse as Santa Claus with a Salvation Army Christmas kettle, an illustration that actually has been seen also on a later Grenada 1983 FDC. The cover is unlisted in the SA FDC catalogue.
General info about add-ons: Uncacheted First Day Covers that have an added cachet is usually called an “add-on” cachet. These are done after the stamp has been issued – usually several years later. This cachet can be either hand painted – hand colored, computer generated, rubber stamp ink, sticker added or even printed on a press. However created, the cachet “enhances” the cover and usually makes it quite attractive. These add on cachets are usually done in small quantities and thus are really quite scarce! The value of an add on cachet FDC is simply determined by the market place – what one will buy. Many artists are now painting cachets on older issues and have quite a following. Auction prices can be quite high! (Source: US FDC seller dwa7)