Well yea u could reuse the tweeters. U just have to find the x-over and 6.5" that goes along with it. Sometimes it's just easier to buy a complete set. OR if want, leave the tweeters connected to the original audio wire and when u buy a new component set, install the new tweeter and connect it to the amp. Then you'll have a higher output.

who ever said crossovers on the amp were bad? almost all amps come with a built in crossover.