[Wild Skies]

I've also heard of the four different qualities or grades of Repro wood used and would like to learn more about them . . .

As for the variation in coloration of Repro wood I believe it has as much to do with the different species of walnut used as anything. Parker Reproduction brochures mentioned that Claro and French (California English) walnut were used--maybe there were more? With Claro you see a lot of color variation from light yellowish brown to very dark reddish brown. Examples can be relatively plain grained to outrageous. Fiddleback, feather crotch, swirling grain, hi-lighting and smoke are commonly seen with Claro. French walnut usually seen on Repros tends to be more conservative in grain pattern than Claro. French walnut typically has black mineral streaking with wood ranging in color from light yellowish brown to medium reddish brown with very little to no fiddle or the outrageous figure usually associated with Claro. French walnut with feather crotch is sometimes encountered with Repro wood, but I wouldn't say that it's common.

Those are my perceptions, hopefully others will add their's.