I haven't seen them anywhere. If it is your dram that is bad your best bet would be to remove the dram module from the UFO, get the part number off the dram chips so you can get a replacement and find someone skilled in soldering SOJ chips to replace them.
In my 32Mb module there are 2 dram chips. Try changing one, see if the problem is fixed, if not change the other one.
Be careful plugging the module back in that you put it in the same place it was removed from. There are more pins in the socket than there are on the 32Mb module so you could do some damage if you misalign it by one pin.