Shopify Shipping App Creation

Looking an experienced Shopify developer to write an app that essentially imports all products and variants and allows the admin to set a different flat rate shipping rate for each item in the store per country. EXAMPLE: Product 1, Variant 1 - US $3, Canada & Mexico $6, All other countries $7.50 Product 1, Variant 2 - US $4, CA/MX $7, All Other $9 Product 1, Variant 3 - US $9, CA/MX $12, All Other $22 Product 2, Variant 1 - US $0.49, CA/MX $1.49, All Other $4.99 At checkout, each individual item rate is added together. If someone bought all 4 of these products above, shipping rates would show as: US Address: $16.49 Canada/Mexico Address: $26.49 Other Countries: $43.49 Looking for completion within two weeks. Either you can write this code or you cannot. No need to drag it out for weeks. Any external code needs to be hosted on my AWS server. Have dedicated domain with SSL installed and ready to go. This bid will be for private app. Reasonable bids only. I do have an interest in making this app public, but we can look at that as a separate project, as I do understand that this involves additional work.