H1B visa stamping — in Canada

Hi, I did my UG in India and my MS in USA. I currently work under OPT STEM extension. I will receive my H1B soon as it has been picked and approved. I will receive the I797A document. I will need H1B stamping if I leave USA to re-enter. I have been informed the H1B appointments in India are not available till late 2023. So can I get the stamp from Canada ? I think Canada also has the drop box system for H1B stamping. Is this allowed? If so, is it a risk ? I have an immediate necessity to go to India after 2 months. Any info would be helpful ! Thanks !

You can do first time H1B stamping from Canada. It should be ok as you have US masters degree.