If you get real bored you can make up some wooden boxes, fill with concrete, take box off, then arrange these concrete blocks about to gap to/from/whatever. Railway sleepers can be found sometimes on the cheap from farmers. If your area wasn't affected by foot and mouth many farmers may have loads of sleepers lying about. Many farmers were forced to buy these sleepers to use as fuel for burning the culled cattle. If you didnt get foot and mouth in your area, they'll still be lying about.
Histroy lesson for you too, 2 for 1.