Eastern Arms was a trade name used by Sears Roebuck in the first half of the 20th century. The guns were made by a variety of manufacturers in the US and Belgium.
Eastern Arms Company was a trade name used by Sears Roebuck. The guns were manufactured by Meriden Arms, Iver Johnson, Stevens, Savage, and probably others.
I can't find a cross-reference for that number, but Eastern Arms was a trade name used by Sears Roebuck. Most of the shotguns were made by Stevens/Savage.
Eastern Arms was a brand name sold by Sears Roebuck. The Model 1929 suggests that it was made by J. Stevens Arms Co.
I find no listing for "London Arms Co." Provide more information or take the firearm to a local gunsmith for a professional appraisal.
Blue book of gun values
Your best bet is to copy the serial number and include it in a letter to the company if they are still in business. They should be able to pass you more information.
Here's what little I can find in the Standard Catalog. Incorporated in 1902. Used the names Union Fire Arms, Union Arms Company, Illinois Arms Company and Bee Be Arms Company. In 1917 the company was either bought up or absorbed by Ithaca Gun Company. They manufactured slide action shotguns, hammerless doubles, a few single shot shotguns, and a couple semi-automatic pistols.
The company that is listed in the related links IS NOT the Buffalo Arms in question that made Buffalo Arms Derringers. The company went out of business long ago, and there are no known websites, or information regarding them.
Your best bets will probably be e-gunparts.com, gun shops, gun shows.
This was a trade name distributed by Shapleigh Hardware of St Louis on shotguns made by Crescent Fire Arms (1892-1931) and J. Stevens Arms and Tool Company (1886-1916).
CRITERION BARRELS is in the Small Arms industry in RICHFIELD, WI. This company currently has approximately 20 to 50 employees and annual sales of $1,000,000 to $4,999,999.
Eastern Arms was a Sears Roebuck brand name in the early 20th century. Possible manufacturers include Andrew Fyrberg, Meriden Firearms, J. Stevens, and Iver Johnson.