there are several listed at gunbroker.com
Your Winchester model 37a was a reintroduction of the model 37 which occured between 1973-1981.That is when your model 37a was made.
Blue Book of Gun Values
A 20 guage WInchester 37A youth model will go for between $100-150 USD depending on condition.
i cant find no date
Serial # C861323
These inexpensive Winchester shotguns are selling for between 55-140 dollars.
I have had several of the 410 37a youth and full value is 125 to 200 depending on condition
The 37A was manufactured from the mid 1960's to the late 1970's.
can you tell the age of a model 37a 20 gage Winchester by looking at the serial number
50-300 USD depending on specifics
You will have to check the auction sites to see what they are currently bringing.
$125.00 to $200.00 in good working condition.