Online may be the only place left to find one unless you have some used game stores or pawn shops around. The PSOne hasn't been made since 2003 (roughly), after all. However, as Rory said, those 2 games will work fine on a PS2 and is much easier to find.
On a side note, buying online is a lot safer than you think if you stick to well-known sites or, if on ebay, check out a seller's feedback history.