Is there a circuit around you Hidalgo, or a zone of whatever (Quebec Hunter Jumper Association type of thing)? If so, you might be able to come across their program on the website, which would list class costs.
google, google, google....
Found one, but I am not sure if it would be the right zone for you, as it is south west. AERSO (Association Équestre Régionale Sud-Ouest /South-West Regional Equestrian Association)
This show (http://www.aerso.ca/equestran_prize_hj_julaug2011.pdf) under the above area has class fees as $17 each, including tax, plus an office/medical/drug test fee of $25.
In the Trillium circuit here, the kids normally do a schooling round (non judged but still a paid class) plus 3 judged courses. So that would be $110 for the 4 o/f classes and a flat class, plus the admin. So now depending how far the show is will depend on how much trailering is going to cost...$50 to 100, or possibly more. Then at least $50 for coaching.
Then you still have braiding to pay for as well....so $25+.