I know nothing about your pistol.
I do know, however, that you can do a successful job of self protection with nothing stronger than high-velocity .22 Long Rifle rimfire cartridges.
The secret is doing enough live-fire practice to be able to place every one of your shots exactly where you want it to go, even in a save-your-life panic.
Then you aim for the neck and the eyes, I guess.
According to the Standard Catalog of Firearms, your pistol is either a Model 6 (long barrel) or a Model 9 (short barrel).
If it's in brand-new condition, it might be worth $250.00.
Parts, including magazines, will be very difficult to find.