Here is an outstanding 20c red brown stamp showing the mechanized harvesting of Wheat in the Canadian Prairies during the Great Depression. Only a very few of these combines existed at that time. They were used by the very large wheat farms. Most of the harvesting of wheat was still done with horses. The stamp was issued in 1930 as part of the King George V "Arch/Leaf" Issue. The stamp is bright and fresh, perfectly centred and mint never hinged. The book value of the stamp is $140.
I combine shipping. After the first purchase, I add 50c to each additional purchase if completed within a week of the first purchase. After you have completed your purchases, ask the seller to send you a combined shipping invoice to substantially reduce your shipping cost or wait until the seller has sent you the invoice. Make sure to pay the seller's invoice to receive the shipping discount. Do not pay the automated eBay invoice which does not reduce the shipping cost.