There are combo switch + single outlet devices.

Fwiw, Ask this old house had a recent episode that dealt with a similar issue

The are certainly combination receptacle/switch devices.

Since receptacles are usually closer to the floor, having a switch there would look a little odd and may be less convenient but would certainly accomplish you goal. Otherwise you could rewire the circuit to put the switch in a more convenient location, like by the door.

Thanks. I looked up the This Old House episode online but I can't figure out how to install it. They didn't really show that. How do I wire this?

If you decide to go with the combo switch/ outlet route, follow the instructions that come with the device.

The link below could be helpful.
Wiring a combo switch outlet

If you want a switch placed at a normal height, you need to run wire, put in a remodel electrical box and switch.

It might be prudent to hire a local electrician if you're uncomfortable/ unfamiliar with wiring.

Thanks David. This is precisely what I needed. I've replaced outlets and switches before so I'll give this a shot. Leaving the switch at outlet level is acceptable in this case. We won't be using the switch often.