Depends on where you are located.
I will say that white edition is not common as rosewood,palisander or black chrome like the 5000/6000/7000 systems.
Not many is aviable but they do come up with out much wait.
I got a white edition '80s Beosystem 6000 with a Beogram 6006 and a Beocord 6000. Now this is rare but you can never rule out that white edition B&O is impossiple to get. Now I got the system without speakers and even being in Denmark where finding B&O is very easy how many pairs so far that I noticed suitable in white? 3-4 and I got the 2 of them. 1 got thrown out by seller after discovering foam rot.
How many white 5500 for sale?
http://www.dba.dk/asp/soegning/detail.asp?annonceid=55733135 Got a cd7000 but that's 1.
http://www.dba.dk/asp/soegning/detail.asp?annonceid=55893464 Half 5500/6500 so that's 2.
With the 5500 system it's more rare to find it with all 4 units together with the same model number like 5500 and so on.
A Beogram 5500 is not hard to find. 2 in Denmark at present. It might take longer to find a white edition but you will never know how long it will take.