Post an ad on craiglist.
http://newyork.craigslist.org/mcy/You should probably also mention in the ad where the test is since it makes a difference if someone
needs to drive an hour in traffic just to get there:/
There are people that offer a service but there price usually also includes them providing the scooter/motorcycle.
So you should probably get something cheaper then that with your own scooter.
Considering that they are only driving there car after you and not letting you use there bike,
i don't see why you would not be able to find someone for $50.
You could always not mention a price and have them contact you and see there ask price of course.
Thought there is a risk that you don't know this person and they might show up late or not
show up at all or something considering you have no idea who they are.
If this fails maybe as a last option you can try walking to the road test and seeing if someone
else there is doing a motorcycle test and ask if they are willing to help you.
If it's a driving school they might not accept since they are not allowed to get work at the
road test area, but i suppose you can then offer to go to there office and pay and come back
or something.
But i think the chance of finding some one doing the motorcycle road test is low?
I don't know whats the benefit of canceling the test instead of trying this option as a last resort.
And don't forget since your not supposed to ride alone with a permit you would not want
the examiner to see you riding alone to the test.