Hi Clive,
I am not much help with those two I am afraid
0641C9 I believe will be CL604 c/n 5415 ex N295JL cancelled as exported to Nigeria 25/10 but I can find no details on its new ID
43E7EC went M-AZKL after it was M-YHOP. My d/b and Rotorspot both show that it should be T7-*** from 1/15 as you state and that's as far as I can get although I would suggest from the hex and the call sign given that it should be 43E7EC,5N-BSQ,22004,AgustaWestland AW109S Grand,(Miscode)
Many thanks
Alan