I am a gun dealer in Asheboro, NC (Franks gun and pawn). Yes, the Baikal choke tubes will fit. This gun is made by Baikal for Remington. It used to be imported under the EAA name. You can also get tubes at Colonial choke tubes.
Interchanges with Tru-Choke or Baikal style threads
Yes, some of the remington tubes will but not all. I have a remington modified choke in my mp 153 right now.
The Spartan is manufactured for Remington in russia. I believe the company that makes them is Baikal. You'll probably have to order the choke tubes. Standard Rem-chokes won't work. Cabela's sells the choke tubes for the Remington Spartan Side-by-Side, also made by Baikal in Russia.
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For the Stoeger side-by-side shotgun, your best bet would be to use any of the standard Winchester choke tubes. They should fit well for you shotgun.
The shotgun in question uses a standard Tru-Choke.
Rem-Choke
The Ithaca Model 87 uses the Winchoke system model III tubes. The Model III tubes fit flush with the barrel muzzle. Other Winchoke tubes should also fit.
Browning Invector.
Briley makes choke tubes for Yildiz guns but only in 12 gauge Trulock is making them now in standard and extended versions. http://www.trulockchokes.com
All choke tubes are essentialy the same no matter the manufacturer. They are all screwed in at the muzzle. Each Firearm Manufacturer produced a tool, such as a T-Wrench or a hand held clutch of some sort to fit the slots to turn the choke (like a big screwdriver). Some choke tubes are exposed on the end and can be turned by hand. If your's is recessed, it is better to find the tool to change choke rather than damage the choke by using another metal object to change it.