Part discontinued?

[MUDDVOL]

I replaced a brake line last week that was rusted through and noticed that my RABS Rear antilock valve, at least I think that this is what it is called. It is the valve that contains the line that runs from the master cylinder down to the frame and then to the rear of the truck. Anyway, after checking a couple of parts stores for its availability, I called the dealer and was told by the parts guy that the part has been discontinued and is no longer available.
My question for you guys in the know is simple, is this right?
The valve is still good, but if it goes bad what do they expect us to do?
Just curious seemed like a wierd thing to me that a part would be discontinued!

[MUDDVOL]

Any ideas guys?

[mschn99]

Its pretty common....ford and chevy make parts "obsolete"....so if you cant find them aftermarket...ur screwed..... Ive seen parts on a 6 year old car unavailable...