Thanks. These codes also appear in the OEM parts listings for the painted parts of the subject model(s). From everything I've been able to find, these codes are pretty much useless to any other paint mfg/shop as they only mean anything to Honda and Honda doesn't provide vintage paint. As to the part listings, I've identified the following OEM parts in Polynesian Blue:
CB750-K1: -Headlight CASE *PB9M* (POLYNESIAN BLUE METALLIC) 61301-300-020EG (replaces 61301-300-010EG)
-COVER, R. FR. FORK (POLYNESIAN BLUE METALLIC) 51602-300-672EG
-COVER, L. FR. FORK (POLYNESIAN BLUE METALLIC) 51606-300-672EG
-COVER, BATTERY *PB9M* (POLYNESIAN BLUE METALLIC) 83600-341-701EG (replaces 83600-300-030EG)
-CVR, OIL TANK *PB9M* (POLYNESIAN BLUE METALLIC) 83700-341-701EG (replaces 83700-300-030EG)
-TANK, FUEL *PB9M* (POLYNESIAN BLUE METALLIC) 17050-300-040EG
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CB450-K4
-Headlight CASE *PB9M* (POLYNESIAN BLUE METALLIC) 61301-292-020EG
-COVER, R. FR. *PB9M* (POLYNESIAN BLUE METALLIC) 51602-319-000EG
-COVER, L. FR. *PB9M* (POLYNESIAN BLUE METALLIC) 51606-319-000EG
-CASE, R. *PB9M* (POLYNESIAN BLUE METALLIC) 17231-294-020EG
-CASE, L.

(unable to document)
-TANK, FUEL *PB9M* (POLYNESIAN BLUE METALLIC) 17050-319-671EG
Obviously it would be more cost effective to locate a fork cover or headlamp bucket than a gas tank... but this is as far as I've been able to get. No luck with the usual places such as CSMNL, David Silver Spares, Western Hills Honda, Ohio Cycle, etc...
If anyone knows otherwise on any of the above, I certainly don't mind being 'educated' - Thanks!