PRO TOOLS 10 and CPTK

Hi all, so here is my dilemma. I am having several issues, and was told just to upgrade. My main issues was that I would open my client AAF files and sometimes get the "missing renderings" message. Some of their tracks were present, but missing audio. No one can seem to answer what the problems is, and all I get is "Upgrade from PT 8 LE to 10". Well, I am ready to do that, but I also need the CPTK so I can continue to cut and paste Video files in the session. Well, CPTK is no longer available. I need to know what my options are. I don't have thousands of dollars to spend on a full HD system...can anyone suggest an affordable upgrade path? I have and iMac 27 2.7 GHz i5, 32Gigs - PT 8 with a Digi-002. If I upgrade to 10 and can't obtain the CPTK, will using a mojo allow me to cut and paste in PT 10? If I purchase 11HD, do I need to have the HD hardware? If so, what hardware? I am at my wits end, and I'm really hoping someone can help here. Thanks for your time, Kim