Technically, it's better to use a thread chasing tap as it does not remove any metal.
However, if you did use a 7-14UNC tap you will be ok. i have done the same in the past when I didn't know any better. Just use plenty of thread sealer when reassembling. Here's the chasing tap.
http://www.google.com/products/catal...ed=0CHMQ8wIwAw#