re: Anywhere to get kaffir lime leaves in BR?

Try the freezer section of a large Asian grocery--sometimes you can find 'em near the frozen banana leaves. Or call your favorite Thai restaurant and ask where the resto sources kaffir lime leaves; they might even offer to sell you some. I have a kaffir lime tree in my backyard, if I were closer to BR I'd happily give you some. The young leaves are best for cooking.

Lemongrass will give you a similar flavor, but not exactly the same...its key essential oil is citral, whereas kaffir lime's big flavor component is citronellal (which smells like cleaning supplies, as it is used in lysol, etc).