There are plenty of 1917s out there that have already been chopped. Wait and find one of those.
I've been trying to find a 1917 barrel for a year or so.
One just sold on eBay. They come up fairly frequently for $150 or so.
I'd do #3. If that Brazilian is nicer than most, that's worth saving, and add to that the fact that it has military pedigree. If #2 is original, with that number it probably saw duty during WWI. To me, that carries value.
If #3 is already refinished, then you won't be hurting it much- might even get away with a chop job and cold blue the muzzle?
I definitely vote for Wiregrassguy's idea.
How short are you going with the barrel?