How Long I Can Receive The JR Pass Voucher

Hello there,

I will leave Canada on March 17 morning & arrive in Japan on Mar 18 around 4pm local time in Japan.

If I order the JR Pass now, how long it will take to mail or send the JR Pass Voucher to me that I can redeem for the actual ticket in Japan?

As I am foreigner tourist, can I purchase rhe 7 days option JR Pass ticket in Japan when I arrive at Narita Airport OR I have to purchase the JR Pass in advance when I am still in Canada.

Thank you!
H T