You can sbr a cp33.

Came here to say CP-33.

Who makes that stock?

Farrowtech. It weighs 3 ounces.

You can get 50 round drums for the Ruger 10/22.

What's the rest of that sign say?

Feather Industries AT-22 is similar.

I wish Kel-Tec would make a 22lr CMR. The CP33 is great but a compact rifle version would be great also.

There are a couple of members over on the KTOG forum that had custom 16" barrels made for their CP33's. I to wish that Kel-Tec would make a 22LR version of the CMR30.

And 17 round extensions from keltec, which makes it 50 rounds.

And 17 round extensions from keltec, which makes it 50 rounds.

Oh man I like that.  Does it run well?

Yup, I've built 3 out.

But one still has a Ruger.........................  

PMR-30 is a hybrid blowback, not aware of any .22lr pistol that fit that bill.
CP-33 is a great pistol and as close as I can think of, but a lot bigger than the PMR-30. And straight blowback.
Closest pistol I can think of that fits your criteria is a Sig p322. Very light, compact, and flush 20 round mags and 25 round extended mags.

Or a Taurus Tx-22. Good reports but god help you if you need warranty work.

I own a PMr-30, CP-33 and Sig p322. FWIW the CP-33 hasn't had any issues but the mags are picky, recently tried loading some CCI mini mag 36 gr varmit hollow points and they jammed up while loading up the mag. minimag 40 gr target round nose is fine.
The p322 had issues with light strikes, the shim trick helped a lot but still has some light strikes with certain ammo. But I've had no issues with feeding or ejecting or locking open on empty. The Sig rear sight is a POS though.
KT p-17 is only 17 rounds but otherwise covers your needs. Never shot one but at that price it's a pretty cheap option.

If an optic is in your plans the CP-33 is hard to beat.

First time I have seen a cp33 sbr with the optic so low. How hard is it to look thru the red dot with a proper cheek weld?

I do not own a CMR30 but do own a CP-33.  On Keltecs website, they state the CMR30 is a “straight blowback”.  What makes it a hybrid?

The CP-33 magazines are the only thing I don’t like about it.  They take awhile to load because they have to be loaded perfectly for it to work correctly.  It is nice because you can add the extension and get a total of 50 rounds from a stick magazine.  There is also a semi decent aftermarket upgradable options for both firearms.