You can probably get away with using the same spokes, but only if you use the identical make and model of rim. Otherwise, you'll have a problem w/ spoke size. If you use the same type rim, an easy way to relace the new one is to tape the new rim to the old one and gradually move each spoke to the new rim. It is recommended you replace the nipples when you replace the rim, but I have gotten away w/ using the same nipples - just replaced a few which were getting rounded.