It’s pretty damn rare in America. They got totally shafted distribution-wise, and it’s Atlus. Over here in ze EU, it’s quite a bit more common. If you can play imports, you might want to grab a copy from over here, though it’s called Shin Megami Tensei: Lucifer’s Call.
It’s 60 euros new here, so I don’t know if you’d actually save money that way.
Google for swapmagic. It’ll run ~$30 but you will then be able to play imports and games on dvd-r. Be careful with games from Europe though, since they often won’t work on American tvs.
Both options have their risks. Swapdisks on a fat ps2 run the risk of killing the drive motor if you get too rough with it, while there’s always the risk of getting a crappy (or worse yet: fake) mod chip if you aren’t careful.
There is a reason why it is so pricey,and that is Atlus almost all of atlus games never drop their price in America since they come out in limited stock at least that is what I believe.