I've been looking into this...
VP does have two coolants, green which is traditional inorganic acid technology (for the inhibitors) and yellow (VCS) which is new organic acid technology. VP's part numbers have changed..P/N 2145012 has been replaced by P/N 22567295. An internet search with this part number will yield several different suppliers.... There does seem to be some other products that cross reference with Volvo VCS:
Shell Rotella Ultra Extended Life Coolant (Yellow, Heavy Duty, Organic Acid, Extended Life)
Chevron Delo Extended Life NF (Yellow, Heavy Duty, Organic Acid, Extended Life)
Peak FINAL CHARGE® Global Extended Life Coolant / Antifreeze (Red, Heavy Duty, Organic Acid, Extended Life)
I probably wouldn't mix any of these, but with a complete cooling system flush and fill, these products seem to be reasonable substitutions.