If you're the least bit mechanically oriented, fungus like you have shown can be cleaned up quickly with a Q-tip and alcohol. If it is on the backside of the front element, a spanner wrench will remove the retaining ring and the front element will fall out. Clean and replace. Only the cost of a spanner is involved. Since the gravity of the problem is less than the one shown in the post I would be reaching for my spanner. I've done several worse than shown and fungus has not returned.
As for buying in HK, if you have ever been there it is one of the most humid places on the earth. I don't doubt NOS lenses from HK have fungus.
Last edited by Fred Aspen; 03-20-2013 at 06:34 PM. Click to view previous post history.