I need a php programmer to modifies or create opencart Extension

I need a php programmer to modifie or create opencart extinsion I have an opencart store and i have an Extension that allows me make products price different for countries by ratio For example product #1 in U.S.A price is 1000$ but i can make it shows in India for 600$ by making the ratio 0.6 but this extension make this ratio for all the products i have a different products and different prices that not all has same ratio I need some how can modifies this extension or he can create a new one, and it should change the prices for the options in my extension it doesn't change the price by the ratio for the product options