PS2 Model 30 memory

I have a friend who wants to add more memory to a PS2 model 30. They are off in the wilds of Oz and acquired this for a good price and would like to just upgrade it to run some programs they have which do not run on modern faster systems. I know this is a snake pit to deal with, and can get more info if someone can get me some information or point me at references for them to look at. What I'm really interested in doing is seeing if just the memory can be had, and it isn't easy to find Sim modules these days, though I suspect there are metric tons of them rotting in places forgotten and not recycled yet. anyway any info to get started would be useful. i see there are entire systems on epay, and may suggest just buying one of them and cannibalizing them for their memory should the asking price for the individual SIMM parts be ridiculous. i could buy the system, us the system to be sure the memory does something and send them the memories alone for reasonable shipping. It would also net them a backup hard drive which are very scarce in even good times as well. I'm hoping that the memories were common to other systems and not some oddball special IBM part. Old advertisements that show up on google show a number of people making them, but that doesn't mean they can be found now of course. thanks jim