To remove the barrel on a High Standard Model 66, first ensure the firearm is unloaded. Then, locate the barrel latch on the underside of the frame and press it to release the barrel. Gently pull the barrel away from the frame until it detaches. Always consult the owner's manual for specific instructions and safety precautions.
with a torch
Your derringer was made in the 1960s and 70s.
High Standard
Yes, they made that model
No such Model name.
Which model?
GunParts catalog lists that particular model as being produced by High Standard, but the exact model is unknown, but I suspect it may be a High Standard Supermatic deluxe (if it is an automatic) or a flight King model (if it is a pump). High Standard yes, but specifically a J.C. Higgins Model 10 ... http://www.histandard.info/manuals/sears/bashotguns/index.html
High standard
High Standard
With the serial number that you have provided,your High Standard citation model 102 was made in the year 1958.
Might I suggest contacting 'High Standard'? Do a search for high standard firearms and get in touch with them.
10-200 usd