(And by "easy," I mean "easy for a competent gunsmith to do.")
I have a mix-master Remington 1903A3 in good shape, but the barrel is pretty worn with some pitting. New-in-wrap USGI 03A3 barrels are pretty easy to find (unlike 1903 barrels). Is replacing the barrel on an 03A3 pretty straight forward? Are there other parts that I need to acquire, in addition to the barrel?