We do have a couple of options here in Canada, lab requisition from a doctor or independant testing through an out of country service called Lets Get Checked.
I've used letsgetchecked and its a great service however I do get regular annual bloodwork ordered by my GP also, It all depends on what your intentions are. Any bloodwork done by a Canadian lab like Lifelabs or Dynacare requires a requisition from a doctor, you cannot simply go and request bloodwork be done whether you would pay out of pocket or not. Almost all blood tests in Canada that are ordered by a doctor are covered under healthcare. Letsgetchecked is a service available to us in Canada but the samples that you draw yourself are then shipped via UPS to a lab in the United Kingdom that is not covered & is out of pocket totally.
I suggest that you request bloodwork through a doctor especially if you haven't had any regular testing or checkups, if you don't have one you can always just goto a walk-in clinic. Almost any doctor is not just going to give you a requisition without you having a complaint, concern, or if you exhibit symptoms for which bloodwork would be warranted. Age plays a factor too as they tend to screen or do annual examinations that include bloodwork for those of us that are getting older. The benefit of using the doctor route is if there is an issue then they will do follow up tests to confirm and actually be able to help you if something is wrong.
I have used letsgetchecked for additional and anonymous testing that I did not want on my medical record.