Recommendations for replacing a damaged Usher BE-718 beryllium tweeter

I have a pair of  Usher BE-718 speakers with the beryllium tweeters. I bought them used years ago and after shipping, there was a dent in one of the tweeters.  I could not hear the difference, and money was tight, so I did not replace.  Well, recently the tweeter cracked, so now I need to replace.  However, I'm having a hard time locating a single (or pair) of the original  beryllium tweeter(s).  The new diamond series might be good, but they appear to cost $900 for a new pair... approximately what I could sell the speakers for if they had both tweeters working.  While I like the BE-718s, I'm pretty sure that I do not want to go down the new diamond path.  Any suggestions/ideas?  Someone have a single (or pair) of old beryllium (or diamond) tweeters they want to sell?  Ideas for possible speaker "projects" using the existing cabinet and woofers?  Thanks!