The original Police Carbine (PC-9) was a non-takedown, but requires using P-series magazines. It also has Ruger's integral scope ring mounts, so if you want to put a red dot on it, you'll have to add a Picatinny adapter. And I don't think they had threaded muzzles or reversible bolt handles.
I will say that my zero doesn't shift, not groups open on my new PC Carbine after removing and installing the barrel. The trigger is good, the reliability is exceptional, and the accuracy is far better than I expected. If you just ignored the takedown feature, I think you'd be quite happy with one.