Try eBay
You can find an owners manual for a Savage Arms Foremost model 6670H, 12 gauge shotgun by contacting the company. The phone number to call for the manual is 413 642-4261.
There should be a phone number in the owners manual that came with your shotgun to where you can buy parts chokes etc. If you don't have the owners manual you can easily obtain one from Remingtons web site.
Your shotgun is a Mossbeg 500. made by them for Sears. Go to the Mossberg website, customer serivce, owners manual, and download the manual for your shotgun.
The manual is downloadable from Remington's website.
Its suppose to come with the gun. And are you gonna kill someone?
This model Cross refernces out to a Remington Sportsman 58, introduced in 1956, the Sportsman-58 was Remington's first gas-operated shotgun. You can request an owners manual for obsolete firearms at www.remington.com click on sportsmans library, then downloads, then owners manuals, then click obsolete owners manuals, you will have to register but it is worth it to get the free manual.
Use the link below and follow the instructions in the owners manual
Go back to where you purchased it from.
Try gun shows.
You may find a reproduction on E-bay.They are listing alot of older model shotgun and rifle owners manuals.You could also look at gunbroker.com.
Try want ads and on line auctions.