If you do a google search for Ladder Golf you will find some sources. Or, you could make your own. I did it using inch-and-a-half pvc pipe (about $15 worth), some cheap colored golf balls from Dick's sporting goods and some nylon rope from Home Depot. Total cost was about $30. We also bought a cheap laundry bag from
WalMart to keep it all together. Get the solid core golf balls and I used my drill press to drill a hole through them.