I don't understand the question completely.
As far as I know there aren't any restricted handgun calibers. So anything is obtainable - the only limiting factor is the $$$ you'd have to shell out for it.
It took me years but I've been collecting all my most desired handguns over the past several years. In California you never know when they'll become restricted so I'm getting them while I can.
My latest purchases:
HK P7M8 - being discontinued by HK. They're making only 500 more - each one numbered. I just purchased #357 of 500
S&W M29-10 with 6.5" barrel - the .44 magnum I always wanted. Unfortunately it's the "reissued" version with the lock ... If I had my choice I'd get an early one from the 70s when the blueing was much better. Still, the 6.5" barrel seems about perfectly proportioned with the frame. And it came with the mahogany case, too.
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Well, on second thought here are some guns I want but can't get for various reasons ...
An old artillery Luger - this carbine version would be nice. But I don't have $17,000 to spare for one. You bet if I had one I'd shoot it, too!
I'd like an ar15 "pistol" but California doesn't allow them:
Or one of several selective fire pistols like:
Glock 18
CZ 75 automatic
Or other class 3 weapons:
The lever action Bushwhacker - has 5 rounds of .457 magnum or .50 Alaskan! Shown here next to a .44 for size comparison.