I have the following Ten-Tec crystal filter for sale. It is the 9 MHz, 8 pole crystal ladder filters that works in the Omni V, Omni VI, Omni (Series A, B,C), Argosy, Delta, Corsair and Orion I. #218 (1.8 kHz) $60 Shipped Priority Mail Please respond off the forum. Paul, K5AF