Can you find some woods, such as a national or state park? This might be where a blue gun would come in handy. There are plenty of areas out there that make natural obstacle courses.
Your yard may also be useful, depending on how you use it. If you have an alert cat or dog, wait until they're asleep and attempt to complete a series of noisy tasks in their immediate proximity, without waking them. This will improve your ability to move silently, and won't take up much space because you'll need to move slowly. Tripwires with jingle bells will help to impede your ability to move without making noises.
For more fun, have a friend set the wires up and then you do the course blindfolded. Tie an arm back to simulate an injury or tie your feet together, etc. The possibilities are endless.