Knowing that you have the barrel already, inhand....you need to get the old one "pulled" ( removed) and do NOT try or do this yourself,,,,,,check around in your locale, for a full service gun shop, and get a price, as all it needs is "R & R"....(remove and replace),,should be a fairly easy job for them.....it's the shipping to "who knows where" if you must send it out, and back and forth, will add up ,be more costly than what it's worth..the "overnight,next day air..." sucks, MORE than the cost of the job is my guess........