Pardons Canada: Denied entry to US for pot charge

The police have taken my fingerprints once in Saskatoon in the 70’s. Possession of one marijuana plant. No punishment that I am aware of. I never went to court. Only found out I had a record when I applied for a job in Nelson, BC in the early 2000’s and needed a CRC.

I do not need a pardon, only a US Entry Waiver as I was refused entry to the US at the BC/Washington border because they found a criminal record. That remains in the US border crossing system forever and is never purged.
I only want the US waiver for Travel purposes. I do not need a pardon or the records destroyed.

My mother in law is visiting from Australia, arriving July22nd. My wife is taking her camping in Washington and I would like to join them on the August long weekend. I would also like to drive to Mexico with my brother in November this year.
How long will the process take, and how much will it cost?I would like the waiver valid for 5 years.
As this is a record that is over 30 years old will that make the process easier?

Pardons Canada: US Waivers or I-194 or I-192 can take 6-18 months to approve so its unlikely you will have it by August. The cost to get the waiver approved is $585 USD and you will likely get a 5 year waiver. The fact that your pot charge is 30 years old will not make it any easier but you will most likely get the waiver.

Pardons Canada undertakes all necessary steps and procedures for removing your criminal record, including: Pardons/Record Suspensions, Purges, Photograph & Fingerprint Destruction, and U.S. Entry Waivers.