Yes, but pricey. In my Mini-14 obsession, pre-AR, I must have collected over 20 magazines trying to get it to work: PMI, Thermold, Mason, Eagle, and more. I have heard the factory 30 round is good, but still more expensive than the best mag ever, the Magpul PMag, for the AR.
Overall though, the Mini isn’t as accurate, light, mags aren’t as good or cheap or abundant as the AR, and I have just grown impatient. The AR just outclasses it on every level.
You never know, though. Ruger has been trying to push the Mini further into the "tactical" niche, mostly for police departments. But as you say, the AR stlll outclasses the Mini, which even Ruger has acknowledged by selling their own AR clone (which is being received quite well, last I checked).