just from an internet search, you might try
USComponent.com
----- Original Message -----From: mikem245@...Sent: Thursday, February 17, 2011 4:53 PMSubject: [crumar] Crumar Tone GeneratorDoes anyone know where I can buy IC's for a Crumar Magicvox tone generator, the part Id is SM304 and the mfg. number is 68070134.