5D Mark II

Hi I'm currently using a Canon 450D with a Canon 50mm 1.8 STM, 18-55mm 3.5-5.6 kit non-IS and a Sigma 105mm macro lens. I'm looking for a camera that has a sensor than will allow high ISO up to around 3200-6400 so i can get higher shutter speeds when using a tighter aperture such as F8-11. I...