There is the CNCMSBL. They had a 21 +,35+ and 45+ league when I played. I haven't played since 2009 but I think they are still around. I tried looking online and found some sites but couldn't get contact info.
But I found the national organization site (msblnational.com) and it lists the following info which was as of 2011:
Central NC MSBL 25+/35+/45+
Updated Dec 16, 2011
President: Mike Wilson
(919) 434-5254
mikewilson21@att.net