You can purchase these fresh tropical fruits from Asian Markets and even on Amazon from the fresh market. Lucky you, if you live in Hawaii, as you can find them at the local markets. Alternatively, you can also buy Rambutan fruit canned. Aroy-D has rambutan in syrup in 20 oz (565 g) cans. The canned version you can find at Asian markets and online as well. If you like your cocktails sweeter, you may prefer the canned option as you can use the syrup that the fruit came in to sweeten your drink. In addition, the canned ones already have the pit removed.