This is a "Hatome Uchi-gu" (eyelet setting tool) used for leathercraft and other crafts to fix eyelets (hatome). It's a set of an eyelet setter and a setting base. The size is the standard #200 (200-size), for small eyelets with a hole diameter of about 4mm. It cost 1540 yen including tax at Tokyu Hands (the price tag is attached). It's still sold at this price today. It looks like it has a lot of scratches and dirt, even though it hasn't been used much. I think it was originally like this. It's almost new in terms of usage, so there are no practical problems at all. I'll include a bag of #200 eyelets. There are still many left, as I've only used a very small amount.