I don't know where Shoji is getting his information but I just confirmed that all three AN6XXX ICs for the sl-1200 are directly available from panasonic. The AN6675 is on backorder at the moment but it is supposed to be available again soon. (I spoke directly with a panasonic representative on teh 6675). The 4011 is no longer available from Panasonic but more than likely they do not build this themselves anymore as this is a non-proprietary Nand Gate.
No issues with the SL-1200 mk2 parts at all.
Steve
Edit: Could be Shoji was referencing the original 1200 not the MK2. I don't have a schematic of that one to see if it even has IC's in it. The SL-1300 does not.