Some Congolese sativas have a strong pineapple flavor. Check out Lilly by Original Delicatessen, really great strain but not a lot of banks carry their seeds.
Bros Grimm has some C99 pineapple seeds that he was giving away the other week. If you make a order and request those as the freebie you may be in luck. If not. Just order a pack of the c99xx and you have a good chance of finding your own.