That is not a heavy lens, so a sidekick would handle that no problem.
The trouble is that your ballhead does not have an 'Arca Swiss' style capture plate, so it would not take the Sidekick.
So to accommodate the Sidekick, you would also need a new ballhead, if you are going to be spending that sort of money I would suggest a gimbal head such as the Jobu Jr 2, this will be fine for your lens, and at £184 is a good price for a well made bit of kit.
All you have to do is make sure the camera is balanced so when the tilt knob is released it stays horizontal.
UK Distributor the one at the bottom of the page, or the one above if you would prefer horizontal mounting, but the side mounting one will be fine for your lens.
You will also need an Arca Swiss style capture plate to fit on your lens foot to allow mounting on the Jobu (and any other Arca Swiss style head)
Monopods ... I have a Gitzo one, but any carbon one will be light and do the job, as with everything you get what you pay for.