I paid $200.00 for what the gentleman told me was a 1950 .
It is not recommended to shoot slugs with a power pack chock on a JC Higgins model.
1956
Try e-gunparts.com
Not recommeded for the casual owner. Find a good gunsmith.
NO!! A choke makes slugs dangerous. DO NOT fire slugs through ANY choke, ever. The life you save may be your own.
1957 more likely 1961
corson barrels.com
its worth $300 - $350
Yes- that is what the poly-choke is for.
just bought one in like new condition for 150$
A 1953 JC Higgins shotgun 12 gauge model 20 pump is values at about $150. It was sold by Sears Roebuck.
You don't give us the model, so it is hard to answer the question. Assuming the gun does not have an obvious adjustable choke, the choke is probably not easily adjustable. A gunsmith can open the choke (from Full to Modified for example) or can install internal interchangeable choke tubes (costs around $125).