My local shop had the Cobra Company AH-1W (or was it the AH-1T?*) cockpit interior for $5. Even though it is the wrong cockpit, I think I'll try to add it to my Fujimi AH-1G. That kit's interior (and exterior) is very basic, but it cost me $5 as well. Hopefully it won't look too bad.
*My shop had both the W and T cockpits for $5, I bought one or the other, don't recall which one. The one that didn't come with the new intakes.