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/
I have a Model 67h, The magazine holds 4 with one in the camber.
it has a wood stock with a small chip shotgun is in fair condition
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
best bet for older gun parts is gunbroker.com they sell most everything gun related
the large magazine cap screw has to be unscrewed, after which the barrel simply rotates and slides off the front of the shotgun.
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
The value of a Mossberg Model 500e 410 gauge shotgun overages between $200 and 300. The actual value of the shotgun is largely determined by its overall condition.