I agree that this is a standard sort of civilian Model 1853, not made for the British army, and it has no markings that tell where it was sold or to whom it was sold.
You will find folks who tell you those hash marks on the barrel, bottom of guard, etc. are confederate marks, showing it was rebuilt in the South.
Not true.
These sort of marks are found on most arms that required hand fitting so that the fitted parts could be kept together. It is true that arms converted or repaired by southern gunsmiths may be so marked - but that's true for arms taken apart by gunsmiths north or south!
Look on the bottom of the stock closer to the mark you show and see if you see a name stamped there...most Birmingham arms will be marked there with the name of the actual maker.