We've been to Colaw's in person. It's amazing, and sad, to see all those wrecked/burned RVs. Colaw's had a large number of Airstreams when we were there a few years ago. They go out of their way to procure wrecked Airstreams so I suspect they still have quite a few trailers, but at any point in time they may not have what you want.
Colaw's typically removes any interior and exterior parts they think will be useful to others and stores those parts indoors or under a shed. Things like awnings, front quarter panel protectors, window protectors, propane tanks, some interior cabinetry are common items that might be removed for future use. Anything left inside the trailer will likely not be useable in short order because once a few windows are removed, the door removed, etc. the trailer will be open to the elements.
If you call them or email be sure to follow-up if you don't hear back from them. The staff is very busy and it's difficult to keep up with all the calls and email.
We purchased a storage cabinet with built-in writing table for our Airstream Classic/Excella. They just happened to have one in stock when we called and it was shipped promptly at a reasonable price.