Manfrotto 701HDV to use in portrait
I had the same issue. I just got the 701HDV head recently to replace a broken unit. The 701 is a very nice head - seems like it is excellent quality and also the fluid heads are very smoooooth for video work. It is a joy to use.
I did a ton of searching on the net for L brackets or something else of the nature to allow me to mount the camera 45 deg. for portrait stills. There are options, but I was shocked at how much some of these L brackets are... Just today I found a relatively inexpensive solution:
Manfrotto 234 monopod head 202-340 $25-30
There is also another similar model: 234RC head 202-348 $40-50
The 202-340 is better suited for the task because it is taller and therefore raises the camera higher up from the table, allowing you to tilt the camera 45 deg. for portrait. I mount the 202-340 sideways so the camera can tilt to the left. The 202-340 does not have the quick-disconnect like the 202-348 but the mechanism allows the camera to be put on/off quite quickly IMO. If you still need more clearance, or if you really want the quick-disc. then also get the 323 release plate:
but that will set you back another $40-50. You can mount that on top of the head. I am using a Panasonic G1 but this should also work for the Canon.