That was last year- at the time I didn't have my PR, only RTD and NOD. Your brother will first have to apply for you online ( I think it's the mInistry of foreign affairs) and then once he gets a letter saying you are clear to apply for a visa (this takes about 3 days to get) you can then take this letter along with other supporting documents (RTD, NOD and proof of relationship i believe) to any office that processes saudi visas in canada. These are a list of offices that you can apply through available on the saudi embassy website. Then from there getting the visa is another week. I would say the whole process would take 10-14 days.