Harold,
970 - Black Bucket Seats
WA 3893 - This is the lower body paint code: Aegean Aqua Poly. Most data plate paint codes simply use the 2-digit General Motors paint code, in your case 38 = Aegean Aqua. I've seen a few (like yours) that use the full code for the paint color (WA 3893). I think this is the actual Ditzler paint formula code, as opposed to the General Motors paint code, although one is a subset of the other.
The other codes you have identified correctly
Aegean Aqua was one of 4 Special Order colors, and one of my personal favorites. How about posting a picture of your car?