Is there a legally mandated filing fee and/or deposit?

Canada Elections Act (published 2000-05-31, lastamended 2012-04-01), http://laws.justice.gc.ca/PDF/E-2.01.pdf

526. (1) An application must be accompanied bysecurity for costs in the amount of $1,000, and must be served on the Attorney Generalof Canada, the Chief Electoral Officer, the returning officer of the electoraldistrict in question and all the candidates in that electoral district.

(2) The court may, if it considers it just, increasethe amount of the security.