I have been trying to decide between cocobolo or macassar for my next bow. I like the macassar with a bocote or zebrawood accent. Or the cocobolo with bloodwood. Your are right that the macassar is brown and the coco is red, not sure how that would look together. Bolivian rosewood is more of a dark brown. Looks like 3(?) pieces in the riser? Maybe sandwich a piece of bubinga between macassar or bolivian rosewood?.
Here is a macassar Quest and coco Silvertip. Hope the owners don't mind me posting, they are beautiful bows so I saved the pics and keep looking at them.
Goke, that's a great looking RER!