Seeker, bore-diameter might be an issue. LR uses an outside-lubed heeled bullet, vs. the inside lubed mag. This was one of the reasons that early conversion-cylinder Ruger Single Sixes didn't work so hot, and the Colt Diamondback factory-issue mags were plagued with innaccuracy. Basically, mag bullets are too small for the LR groove diameter, something it took Colt a LONG time to figure out.
Dunno how Ruger addressed the problem in modern re-issues, but converting an older/other LR gun may not work out so great.
FWIW, AMT Automag II's are supposed to be pretty good IF you can get a good one, a big if. They came in a variety of barrel-lengths. LOUD, bright flash, like a 7.62 x 25 or a .30 Carbine pistol.
There's also the Grendel P-30 but I've never seen a good story about these. Biggest virtue was a 30-round mag, but it doesn't make up for it being a very ugly-looking complete POS.
Both of these are full-size guns, so it's probably moot anyhow. Just mentioning 'em as membrs of the short list of available Mag Rimfires.