Hi there!! I had similar problems. Bought a second hand card that came with broken cable. Only place i got a brand new replacement cable was Amiga Super Bit in Spain, very friendly people. Check
www.amigasuperbit.comIf you PM, i will send you a very detailed pic of my "new" cable. Im just in the process of moving to a new flat, so all my Amiga stuff is in boxes at this very moment.
But if i can help you more, just let me know!
Cheers!
Sebastian