Years ago I used a guy in Niagara Falls (US side) who maintained a warehouse that stored items for pickup, I dont recall his name but here is a link to another warehouse I found doing a quick internet search that seems to do the same thing:
https://shiptotheborder.com/new-york...-niagara-falls
I would ship products purchased by me to the US located warehouse then pick up the items on the way back from holidays in Florida to take advantage of the duty allowances. Keep in mind, the CBSA knows of these locations so if you pick up something they will expect you to declare it. I bought a lot of winter clothing sold in the Southern US from folks who never used it, but now I mostly get it from the local Value Village, other than my outer camo layer.