This looks like a toy chainstitch machine called American Girl. I have a red one with a sticker underneath stating it was made by the National Sewing Machine Company. According to Glenda Thomas in Toy and Miniature Sewing Machines Book II, this toy appeared in the Sears Christmas catalog for 1936, and generally dates from the 1920s to 1930s. So it is close to being an official antique. Have fun cleaning it up!