Macbook Pro 13" - swap for - Quad core/8 core mac/imac .

I have a macbook pro fully upgraded with a 500gb HD and 8GB Ram. It is a great machine and has served me well recording music. But I have recently got into video production and I am getting to the point where I need a more powerful machine. I am looking to swap my macbook pro for your mac/imac. Let me know what you have, I am only interested in quad core/8 core machines. If you could please send a full spec that would be great. Thanks. Heres is the full spec of my macbook pro. Macbok pro 5,5 13