Question about American buying goods in Canada

Ethics and guilt about giving the Government money!

Oh come on, the OP is buying a few parts to repair a worn out Camper!

The easiest route would be to have whatever is required installed at the Factory.

I don't think anyone would consider "Repairs" as anything other than maintenance , it wouldn't even be classified as merchandise or Imported Goods.

Of course there will be some folks that would declare the Hot dog they ate at Costco as a purchase.