Chainsaw Repair

alright, echo fans, I have a problem with my saw and am asking you experts for information and help.
    I have a grey body cs-440.   I recently ended up running it too hot and scoring my piston a bit, and now I am worried about my saw.    full disclosure:  I mix my own gas/oil, and NO ONE ELSE here at the house uses my two stroke gas.  I have the chainsaw, and old craftsman 2-stroke rototiller and an echo string trimmer.   I mix it to echo specs, which I think is 50:1.      After my saw started getting silly, I looked up the carb adjustments, and found that it was as far rich as it would go, with the limiter caps on.   I was not comfortable taking the caps off and messing with it.       I checked my gas in my 2 stroke gas can, and it was discolored, almost whiskey colored, with some water in the bottom.   In a glass jar, it didn't take much movement to emulsify the water into suspension in the gas/oil, so I figured that I was running WAY lean and damaged my piston.
     I went and bought 100% gasoline (at a marina, at a premium price) and mixed up a new batch of gas/oil at 40:1 ratio, and put it in my saw.   I started it and allowed it to idle up to temp, and maybe another 5 minutes, then went cutting.   It cut well, didn't have any bogging issues, didn't stall, didn't get "stupid hot".   

      so, getting down to the real issue.   I want to replace my piston and piston rings, but all I can find is the "piston/cylinder kit" from echo, for $200.    Are there any other options as far as that goes?  it was a sub $300 saw when my father in law bought it for me, and I am struggling with putting $200 back into it, when there are used saws with more power, and built for heavier work available for around that.   I am acquiring another saw, but don't want to call this one "junk" just yet.
       More disclosure.     I heat my home with wood, and an indoor woodburner.   I just started getting logs delivered from a land clearing company, and am doing all of the cutting and splitting myself.   I like my echo, it has been good and comfortable to use.   It has been reliable until just recently, but maybe it is not the right saw for what I am doing right now.       So where can I get just a piston and rings?  Help a brother out.

   oh yeah, one more thing, in looking it up, there is a distinction in the line someplace, so the serial number is important.   it is 08064522

         thanks everyone.

Echo Store $59 for piston kit.  http://www.echopartstore.com/pages/OemParts?aribrand=ECH#%2fEcho_%2f%2f_Shindaiwa%2fCS-440__S%2f%2fN%3a_C07013001001_-_C07013999999%2fEngine%2c_Short_Block_--_SB1082%2c_Engine_Cover%2f8710%2f8715