You are unlikely to get any wear on the bore because its plated, so dont ask for the barrel to be rebored
All the essesses have a tendancy to slappy pistons, and the noisy ones are the most powerful !
If you are not using oil, and the noise gets less when the engine (piston !) is hot, then dont worry, they really all do that sir.
If you're really worried, I could sell you some used spares, but they'll be the same within a 500 miles.