I love my 39. So much that I bought a second one. And I'm not rich.
HOWEVER, since the OP asked for the most rugged, durable, no-maintenance, inexpensive .22LR.
To me, that says stainless and synthetic, so that rust and scratches are not an issue. And it says bolt action, which doesn't foul appreciably at all, and will go a very long time without cleaning. It can be cleaned quickly and easily should you get sand or mud in it. Finally, I'd say a detachable magazine is a plus. While I prefer tube magazines and find them to be reliable and simple, a detachable magazine won't get tweaked as easily with abuse as the inner mag tube, the action can be cleaned more easily when you pop it out, and the magazine can be replaced for cheap, in 5 seconds, if you damage it.
While, again, I LOVE shooting my 39's, I'd suggest this gun:
http://marlinfirearms.com/Firearms/BoltAction22/980S.aspx
It has iron sights with a protective hood, too. It is well worth scoping, and will work either way. It won't rust, it can be cleaned completely and oiled in a few minutes, there's no wood finish to scratch, and it costs about $260 brand new.
Now if you just want an inexpensive .22LR rifle that will shoot, and shoot accurately, a base-model Marlin 60 now has a laminate stock and shoots like a certain other brands' "target model", for a good deal less money than the standard 10/22, which I had, but never was real happy with -- mine was not accurate or reliable. But it's blue with a wood stock, and a tube magazine. As a blowback semiauto, it needs to be cleaned or it will eventually stop working at all.
The stainless bolt gun above is relatively inexpensive and, if that's what you want, it will probably take more abuse than anything else for the price.