Yes, you can by Canada Post labels for non-US International locations on eBay Labels. I just tested it with an old transaction to Spain and it was showing the XpressPost International option at 48% off.
There are a few different ways people are shipping to the USA at the moment:
1) Using Zonos/Canada Post. For items with zero duty then no real changes are required aside from needing to buy your label somewhere other than eBay. For items with duty you would need to increase your shipping cost to include the amount owed to Zonos.
2) Using a cross-border shipper. There are various options available depending on the CBS. Some require you to jump through some hoops like uploading manufacturer information including address to the shipment. Both Stallion and ChitChats have a new collaboration with PostNL that supposedly doesn't need the manufacturer information, but it's still too new for any reliable reports on it's functionality.
3) Using a courier like UPS and sending it DDU. This isn't recommended at the moment - there are tons of issues being reported, although it seems like if the contents were "Made in USA" there is less of a risk.
4) Using eIS if you're one of the few that has been enrolled in the program so far. Although there are a ton of issues with this right now as well.
