Let's say I had a NIB 6920 and wanted to swap out for the 14.5" 6921 upper, what would my options be?

Any chance someone might just swap out for me? Or is the 6921 more valuable?

Are there any reasonable options for just purchasing a 6921 upper? Then I guess I could just sell the 6920 upper.

You could purchase a 14.5 6921 barrel and replace the barrel yourself.

+1

You could also have your barrel or cut your barrel to 14.5" and permanently install a long FS of your choice to meet the minimum length of 16".

If you are not going to permanently install a FS you have to have the SBR paperwork first before getting or cutting your barrel.

It's up to you if you want to sell or keep your extra barrel or upper and it will retain it's value if you didn't fire it.

Colt uppers should be available from policesupplyinc.com, Legal Transfers (at EE), knesekguns.com, Hoplite Inc. KY (see Shotgun News) and many other dealers. Also check the EE for 14.5" barrels.

The ARFCOM way is get both.

The 6921 barrel at SAW will cost you $495.00 Are you sure you want to change barrels at that price and will have to add a longer flash to make it 16'' and that will bring the cost up even higher.