Never heard it referred to as that.
There is no such model number assocaited with the Ruger Bearcat. Do you mean the serial number is 918?
ruger bearcat 22 blue and brass serial # 62155
You can request a letter from Ruger.
22
You take it to a gunsmith
Ruger's website has sn data you can look up.
50-200 or so
Check the frame and butt
50-200 or so
50-300 USD depending on condition.
50-500 USD depending on specifics
50-400 depending on specifics