You can fit the Model 1100 or 870 Special Field with any Model 1100 or 870 stock. You must, of course, use 12 Ga. stock on 12 Ga. receivers. On the 20 Ga. any style lightweight stock can be used as the 20, 28 and 410 Ga. stocks are all interchangeable. Keep in mind, some stocks may require a different stock bolt. You can order replacement parts through our parts department by calling 1-800-243-9700 M-F 9am-5pm EST. Order forms and price lists can be found Here. You can also order replacement parts directly through our online store at www.shopremingtoncountry.com.