10 to 1
100-450 USD or so
It will be marked on the barrel/reciever
Try e-gunparts.com
@ 4"
I would start my search at Smith and Wesson first.
Yes.
4.5 or 6 inches
You will need to ask a gunsmith
22LR
Model 37
Only made in the USA
Look on frame inside the cylinder area to find the model number of a Smith and Wesson 357 mag snub 2 in stainless barrel