yeah, no need to spend a ton on that kind of thing IMO. my friends and i used to use a skate deck on top of a slightly deflated soccer ball. your PVC idea could work too, you might want to put something on the PVC to alter its texture though..?
Get a 2x12 and cut it to a little wider then ur stance. Probably abou 18 inches. Cut off a 6 inch peice and screw it into the middle. Will look like T. Or skateboard on 2 liter bottles filled with water are both things I've used.