I don't have first hand knowlege of these answers from Lee or Larry Brown and I know you are looking for specifics Chris but here's a few things I have learned.
The original cone and transition were black. By 1975 Centuri was selling these capsules as the PNC-13E/ST-202. The EnerJet Egg Crate used this same capsule and the EnerJet Egg Crate was also pictured in some of the Centuri "Egg Capsule" ads that state it was black polyethelene.
Some of the fin cans in 1975 were "Centuri Orange" and "Hot Blue". Earlier versions were Red and were used on the Centuri Argus in 1973.
I had some interesting conversation and posts with Jerry Irvine for the short time that the TRF2 forum was in existence, and while discussing the Historic EnerJet Two-Stage rocket that flew at Anaheim Stadium in 1974 (also designed by Larry Brown) Jerry also contributed information and details about other early EnerJet sounding rockets including an original SR1340 that he said he still owned. The molded parts on the original 1340 were all Red according to Jerry.
One thing I can tell you about the rocket in the 4th Ed. Handbook picture, if it is an original EnerJet 1340 the capusule base would have had to have been modifed to fit since the 1340 used tubing closely matching the dimensions of the Semroc LT-125 with a smaller ID than the ST-13. The capsule would not have fit because it was designed for ST-13 tubing. I built mine pictured below and used the Semroc LT-125 and did modify the capsule base to fit. If you look closely you can see a seam in the LT-125 tubing where I had to cut the capsule base and the tubing to allow this mod. and a short length of 1.25" dia dowel.
Determining exactly when that 4th Ed. Handbook picture was taken would help to determine the correct color of the fin can. I guessed at Red color based on the 1973 Centuri Argus because that's the earliest color photo of that fin can I could find and what I learned about the original EnerJet 1340. Perhaps someone else can contribute some more information in this area.
I hope this helps Chris. I always thank Sean for how well my SR1340 came out. It was his post and picture that brought me to YORF while searching for information on these early EnerJet rockets last year