That'll be your call. A lot of people just put rings in. In my opinion if you have enough hours to wear out a set of rings, I'd be putting pistons in too. Rings are $40 or so and you can find a piston kit for around $130. Why have to replace the engine for $90 that you could spend now? Just an opinion.
When a piston fails the skirt breaks normally. The pieces go through the crank, clyinder and damage the head. Spend the extra $$$ now and save in the long run.
Oh, what it your altitude. Maybe your compression isn't really that bad. A way to tell if your rings are worn is to put a tablespoon of oil in the cylinder and re-do the compression test. If the numbers stay the same your rings are most likely fine and the gauge may be off. If that's the case, I don't see a problem because the cylinders have the same compression..... Again, just my opinion.