The labour dispute between Canada Post and its workers continues with both parties at the discussion table, but many small businesses in Calgary are worried about how a work stoppage could affect their bottom line.

Both sides agreed to extend the mediation by another 24 hours late Monday night, just before the union was set to put a rolling ban on working overtime in place.

Two Calgary businesses that CTV spoke with said that a postal strike would make it hard for them to get goods to customers and stock their own shelves.

Linda Perry, who owns Soul Food Crystals & Books., says a reduction in postal service could impact selection for customers at the 17-year-old business.

“We do have some distributors in Canada that we buy from and, of course, some of them use the post office,” explained Perry.

The West Hillhurst store, which sells self-help books, crystals, jewelry and tarot cards, faces uncertainty when it comes to securing goods.

“How am I going to get product?” asks Perry. “What’s it going to cost me?”

Fairgoods, an online shop owned by Lauren Stanley, has had to look for other ways to ship merchandise if and when a Canada Post strike comes into effect.

Stanley sells novelty items for special occasions, including weddings. She says many of her customers are worried that their orders won’t get to them if there is a work stoppage.

She has been able to find an alternative for shipments coming out of the United States but, in Canada, she’s out of luck.

“When it comes to Canadians, I’ve had to just say ‘if you want, I can look into couriering it to you, but we are looking at costs that are probably three or four times what you’d normally pay because all of our stuff is really light and you don’t generally have to pay a lot to get it to people in a timely manner. It’s making it hard. The Canadians are the ones that are really losing out.”

Canada Post has been bargaining with its employees for more than nine months, but both sides were far apart as of late last week on key issues including pension changes for new employees and pay scales for rural postal workers.

CUPW had said it would begin job action on Monday by having its members refuse to work overtime on a rotating basis, starting in Alberta and the Northwest Territories. That plan was halted when both sides agreed to a request for more time from a special mediator, who was brought into the dispute Friday.

The union then said job action in the form of a refusal of overtime would begin in British Columbia and in the Yukon on Tuesday morning if no settlement was reached with Canada Post.

CUPW said that plan "has been put on hold for another 24 hours."

International online seller eBay has also stepped in with a campaign to urge sellers to write to the Prime Minister urging him to pass legislation to put an end to the ongoing labour dispute.

The company says that a disruption would result in a massive impact on small and medium businesses in Canada, so Trudeau should intervene.

If discussions do fail and the mediation isn't extended on Tuesday, it doesn't mean that mail delivery will stop.

Workers say they will refuse to work overtime and that will result in a big delay.

(With files from The Canadian Press)