Davis Industries of Chino CA did, however, they closed in 1998.
No known published data
We need more information to identify the model. Colt's original single-shot derringers were in .41 caliber, not .22. They did make small single-shot derringers in the 1960's in .22 cal, but they did not have the markings you describe. www.countrygunsmith.net
There is a dealer I know that is knowledgeable about these Omega Derringers. You can contact him at 804-271-0003 and he will tell you.
AFAIK, no.
No
yes a 50 cal.
Given the right circumstances and shot placement, any of them
Based on proofhouse.com, second model derringers in .41 cal with serial numbers 1-9000 were made between 1870 & 1890.
Any .177 cal pellet can be shot from you air rifle. However you will find that some brands are much better than others.
how much is a 22 cal single shot rife by w.h davenport worth made in 1891
Wee Wee!
Ruger did not make firearms in 1934