Jeff. When you buy something, the seller will calculate the shipping cost to your address. This is your resposibility. You can negotiate which company the seller will use to ship your item.
What you are being billed for is brokerage fees and/or duties. How can the seller be responsible for this??
I have received some items with a $0 charge and other items with a $200 charge. The charges are based on a number of factors ranging from the shipper that is used and the value of the parcel. Again, I have had a hundred packages sent to me over the years. The seller never pays for the shipping, nor the associated charges.
You can have your parts shipped without brokerage fee if you have them shipped "air". This is usually 3 times the money of regular shipments. You pay at the beginning or at the end. Either way, the BUYER pays the costs.