The doubles I've seen labeled by this name were made by Francisco Anitua and the sidelocks seem to be selling on Gunbroker for $300.00 in good condition. However the reviews I have read from owners were all positive.
Google.
70-100 years.
It is a single barrel, break-away 12 gauge shotgun.
depending on the make, age,and condition that shotgun could be worth nothing up to $3000.
There is no "break in" shotgun. A "break open" shotgun is a single barrel, double barrel, or combination rifle/shotgun which breaks open in the sense that a lever will unlock the action, allowing the barrel to pivot at a hinge at the front of the receiver, pivoting the rear of the barrel up to expose the chamber. A shells may be loaded into the chamber and the barrel pivoted back to close the action. The act to "break in" a shotgun means to fire it a few times to loosen it up.
Seek the services of a good gunsmith
The Remington 90-t is a 12 gauge, single shot, break open, trap shotgun
$50 and up, depending on make, model, and condition.
my serial#i s 612fb
No published sn data
The CBC MODEL SB 410 BORE SHOTGUN is made in brazil and imported by firearms import and export Corp. located in Miami, Florida it is a break-action single shot shotgun
Assuming you mean a top break shotgun, there were several models, prices will vary. For a single barreled top break, about $70-$75