I'm not sure if we are talking about the same part. I've never seen them in anything other than black. It is the garnish trim on the inside of the car that is on the left and right side of the windshield. I would suspect the same part fits all year NSX's. On my 01, the original trim piece was much softer and spongy. The bubble appeared to be caused by an air pocket developing between the vinyl outter layer and the foam core. The new piece seems to be much different. The soft spongyness is gone. It is more like molded plastic, although it is still somewhat soft. Clearly it has been reengineered. At less than $100 each, the price doesn't seem out of line. If your car still has warranty, get them to replace them free.
btw. The bubbles are much more pronounced when the interior is HOT. I think that is when the air pockets expand and make them more pronounced.