A few hundred to a few thousand USD depending on EXACTLY what configuration you have and its overall condition.
Christopher Miner Spencer
Try search for Spencer rifles- it was an early lever action repeating rifle from the period of the US Civil War.
Serial numbers are located in various places. Try the breech/action. If it's not visible it could be worn.
.58 caliber Springfield musket .69 caliber Harpers Ferry Rifle '''Spencer carbine '''Henry repeating rifle '''Colt revolver '''Remington '''English Enfield rifle ''''''''''''''''''
You are probably thinking of the Spencer. A lever action rifle, known as "That Yankee gun you can load on Sunday, and shoot all week.". to quote one Confederate soldier. See the link below for more information on the Spencer.
Not the first, but one of the most popular- the Spencer.
Depends on condition, variant, etc.. Range from 200-2000 Depends on condition, variant, etc.. Range from 200-2000
Oliver Winchester made the first Winchester Rifle(repeating)
Oliver Winchester invented the Winchester repeating rifle in 1860
The Union cavalry was the primary recipient of most Spencer Carbines. They were useless in the hands of the Confederacy because the South lacked the means to produce the metallic rimfire cartridges used by that firearm.
1860
No