A stripped PSA or Spikes barrel (both are FN) will run about $160-200 depending on your flavor. 1-7 is standard USGI twist but there are some advantages with 1-8 and 1-9 especially if you run a lot of 55 grain M193. If you want a barrel with a FSB you'll need to add about $50 to that price.
All you need is a new bolt not an entire BCG. So about $60 for the bolt.
And someone to screw the barrel on for you...
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