Welcome to the forums! I'm pretty sure you can just hold a polarizing filter in front of the lens, but unless you have 3 hands, it will not work very well (in an ergonomical sense). Also, you might be able to use a regular polarizer instead of a circular, because of the autofocusing method used. I'm not entirely sure on that one though, so don't get mad if it doesn't work.
My best advice is to head to a camera store, ask for the smallest filter they have (40 mm maybe?), and just try it. Try a regular polarizer first, and if autofocus doesn't work, try the circular.
Also, there might be adapters available for your camera but you'll have to research that yourself