https://www.canadapost-postescanada.ca/cpc/en/business/small-business.page?
Gets you a Solutions for Small Business number immediately, I believe.
A card arrives later in the mail.
You can probably also get it at the post office counter-- not at postal outlets though.
There are some discounts and Expedited service becomes available. This is a business service and not available otherwise.
Plus the October free shipping, maybe.
The prepaid credit/gift card may be the solution otherwise.