The chokes look like Win-chokes, made by Winchester for their shotguns, and also fit Weatherby and Mossberg shotguns. They came with various restrictions from extra full turkey chokes to cylinder bore. If that is what they are, you are fortunate because they are readily available and they come with a choke wrench that has a half circle, with a peg at the end of the circle that fits into the small hole, visible in your photo. Keep yer powder dry.......Robin