I don't know whether all new Yorks are black but they have been available that way for years. They were sort of like a generic out the back door project for years. It may be the only way to get them anymore. I wouldn't worry about it.
The reciever-drier is a reservoir/filter/descicant device that should be replaced every time the system is openned according to MB. In humid climates such as Florida it is specially important.
To replace it one must evacuate the system, replace the part, and reevacuate and charge the system.
Bosch Master, ASE Master, L1
33 years MB technician