a while back i upgrade a powerbook 1.67 g4 to a hitachi 7200 rpm 100gb disk. the reviews back then (and still) say this was the faster of 7200 rpm pata 2.5 inch disks. here is the model number HTS721010G9AT00 (0A25015) hopefully stores still stock it. good luck.
Some of the newest 5400RPM drives surpass older gen 7200RPM drives while maintaining lower power consumption. I think Tom's did an article on it a while back. You should be able to get some of those drives in PATA flavor.