build a website to sell T Shirts under different categories

want to have a website selling T shirts. there will be a number of categories of shirts - say up to ten. Each category will have its own page/s where buyers can browse the selection. It must be easy to add and remove shirts from the offering. Categories should have say a max of 100 shirts. So a thousand shirts available to browse through. Not all 1000 will be available initially so the pages must be dynamic the selection will grow over time. Need shopping cart. Each shirt should have a size selector with up to 5 sizes but a single price for each shirt.. As customers will be international must be able to select postage for different regions.