I have been looking into this myself. Father passed away, got hit from him, but no magazine. Looks like it may be very close to a mossberg 185 20ga. See related link for a web site that has them for the Mossberg. I remember using this gun as a kid and this looks to me like the same design. I'm planning on ordering one myself. ($37.05)
I got my in 1960 from monkey wards
Try http://www.canadiangunnutz.com/
To remove the magazine tube from a Charles Daly 20 gauge shotgun, first ensure the firearm is unloaded and the action is open. Locate the magazine cap at the end of the magazine tube, unscrew it counterclockwise, and then carefully slide the magazine tube out of the receiver. Depending on the model, you may need to remove additional components, such as the forend or any retaining screws, to fully detach the tube. Always refer to the specific owner's manual for detailed instructions related to your shotgun model.
it has a wood stock with a small chip shotgun is in fair condition
I have a Model 67h, The magazine holds 4 with one in the camber.
Your shotgun was made for Sears by Savage, and is their Model 18 Shotgun. Magazines are available from gunpartscorp through their website. The part number is122990B, and the cost is $32.75 plus shipping
Actually the shotgun uses 16 gauge shells i have the same shotgun
Marlin Model 49 Exposed Hammer Pump Shotgun, 3000 made 1925-1928 for stock purchasers only, 12 gauge 2 3/4" with 30" barrel, 4 round magazine
the large magazine cap screw has to be unscrewed, after which the barrel simply rotates and slides off the front of the shotgun.
best bet for older gun parts is gunbroker.com they sell most everything gun related
You can get a clip or magazine for a 20 gauge model 228 Kessler shotgun from one of several gun parts catalogs. These include Cheaper Than Dirt and the Numrich catalog.
Bluegrass 12 gauge shot gun model 1900