Get a copy of the Gun Digest Asembly/Disassembly instructions for centerfire rifles. The Marlin Mod 36 is included.
Beretta would be a place to start, then want ads, gun shops, gun shows
The 469 is very similar to the 59, 459, and 669. Gun Digest publishes an excellent series on Firearms Assembly and Disassembly and the Part 1 Automaic Pistols volume includes excellent instructions on disassembly of the model 59 series.
About $225 used.
The Gun Digest Book Firearms Assembly and Disassembly Part 5 Shotguns has an illustrated description of the model 97 disassembly.
It was made between 1934-1946. 100,030 made. No serial numbers. Your best bet is to find a copy of The Gun Digest Book of Firearms Assembly/Disassembly: Rimfire Rifles by J.B.Wood
Find a copy of the Gun Digest Asembly/Disassembly book for rimfire rifles the Model 190 may be in there with detailed instructions. If that fails, contact a local gunsmith.
A Sears Moels 300 is a Winchester Model 1400. For a manual, go here: http://www.stevespages.com/page7b.htm For disassembly instructions, get a copy of Gun Digest Assembly/Disassembly for shotguns. Aslo, gunpartscorp.com has an on-line exploded diagram for the model 1400.
Gun shop, gun shows, e-gunparts.com
Why would you want to? Oh well, it's your gun and I hope this helps: http://www.rarewinchesters.com/images/Exploded%20Views/1866-73-dissassembly.shtml
A schematic is available at gunpartscorp.com. Disassembly instructions should be available from Remington or the Gun Digest book of .22 rifle Assembly & Disassembly. Look for it on Amazon.
First, determine which model Winchester 12 gauge you have. Then go to www.stevespages.com/page7b.htm and download the manual. For a more detailed set of disassembly instructions, go to the Gun Digest bookstore www.krausebooks.com/category/firearms_knives and buy the Gun Digest Assembly/Disassembly book on shotguns.