This is my first post, I have been reading for a while. I mostly cut fallen oaks for firewood on a Texas ranch where I help a friend. I started with a Makita DCS 540 that I bough 10+ years ago for $50. On Black Friday I bought my first Stihl, a MS250. Since then, I have picked up several used saws, mostly super cheap, a MS461, another 250, a 193t, and the rancher gave me 2 Echo CS-310's (that I got running and sold) and I recently picked up a 357XP for $100. The 461 has more power than I will ever need and the smaller saws take care of the smaller jobs just fine. I have ZERO need for a custom saw but reading about ported/big bore 357's has caught my attention. From the SN I believe my saw is a 2005 with auto decompression. What kind of $$ would I be looking at for a new ported & polished top end and muffler mod, and who can do it? Thanks for the wealth of information!