I would start my search at numrich gun parts corp.They can be found on the web.I would also contact Marlin Firearms company themselves and see if they possably have one in stock?
ableammo.com has them for $13
They don't have clips. They have magazines. You can order them through Numrich.
Factory magazine for Marlin 80 DL $18 + $7 shipping at ammoclip.com
I have Been told that this gun is a copy of a marlin 80 and that clip Should fit it but this is just heresay
Glenfield was made by Marlin. Check with a local gun shop.
You can get them from Marlin....
Where Can I Buy A Clip For A1966Enfield Rifle Where Can I Buy A Clip For A1966Enfield Rifle
try looking at gun shows. you will probably find several parts for it there call marlin them selves i just orderd two clips for my marlin 25 bolt at 12.50 each. if you buy two there is no shiping chage i takes about a week 1-800-544-8892
you can buy it online on creaclip.com
That is the T-900 system, restricted by Marlin. email@example.com