Try e-gunparts.com, local gun shop, local gun shows, etc..
straight from marlin
Factory magazine for Marlin 80 DL $18 + $7 shipping at ammoclip.com
The Marlin Model 795 rifle does not utilize clips, but has a 10-round detachable box magazine. The rifle itself has a magazine disconnect, and thus will not fire unless a magazine is inserted.
I have an 80 G rifle but no clip. I would be willing to sell the rifle without the clip.
It was made by Marlin and is a pre-war version of the Model 80.
Glenfield was made by Marlin. Check with a local gun shop.
The rifle was made by marlin in good condition its worth about 100 dollars. These are usually good shooters as are most Marlin rifles; its it a keeper. It is also known as a Marlin Model 80. Clip is still available for about $16 directly from Marlin.
The Marlin Website (http://www.marlinfirearms.com/) or any number of 3rd party website (www.cheaperthandirt.com, midwayusa.com, etc)
The price for a Marlin WestPoint 701 .22 caliber rifle depends on the condition. One that was sold in an online auction went for $80.00 and came with one clip.
150 USD
ableammo.com has them for $13
Copy this link for the Marlin model 56 magizine/clip: http://www.e-gunparts.com/DisplayAd.asp?chrProductSKU=195950A&chrSuperSKU=195950&MC= The above site " Numrich" has the Magizine for this Rifle. The link should go right to the clip. Also this site has the parts blowup for this Rifle and many parts for it also.