Got a call from this number then not even 5 mins later got a call from a 314 area code. If I don't answer one, I'm not going to answer the other. I think I'll go with sambo's idea and answer with a coach's whistle next time they call.
To minimize the annoyance from these people, save the number in your phone book with a silent ring and the name Z so it appears only in the bottom of your phone book. That way when they call you don't even hear the phone ring and if you do notice it the Z tells you it is a spammer who you can ignore.