I converted my Canadian license to Qatari 3 days back. It is an one minute job. You need 250 riyals, copy of RP, a letter from the company and 2 passport photos. You have to go for an eye test, and then you are ready to exchange your license.
Till you get your RP, get an international license from CAA, because with Canadian license you can drive only for 7 days from the date of arrival.