using a static cart, you will need to do things slightly different, set the price column to be updatable from a select list and set the option column to be updatable from a hidden element.
set the label in the price list to show the option name and the value to that options price.
then use javascript to populate the hidden element with the selected options label.
an example of the modified add to cart form would look like this:
<form name="WA_Store_Cart_1_ATC_10" method="POST" action="<?php echo $_SERVER["PHP_SELF"]; ?><?php echo (isset($_SERVER["QUERY_STRING"]) && $_SERVER["QUERY_STRING"] != "")?"?".$_SERVER["QUERY_STRING"]:""; ?>">
<input type="hidden" name="WA_Store_Cart_1_ID_Add" value="10" >
<input type="text" name="WA_Store_Cart_1_Quantity_Add" value="1" size="4" >
<select name="WA_Store_Cart_1_Price_Add" onChange="document.WA_Store_Cart_1_ATC_10.WA_Store_Cart_1_Options_Add.value = document.WA_Store_Cart_1_ATC_10.WA_Store_Cart_1_Price_Add[document.WA_Store_Cart_1_ATC_10.WA_Store_Cart_1_Price_Add.selectedIndex].text">
<option value="5">option 1</option>
<option value="10">option 2</option>
<option value="15">option 3 </option>
<option value="20">option 4</option>
</select>
<input type="hidden" name="WA_Store_Cart_1_Options_Add" value="option 1" >
<input type="submit" class="eC_FormButton" value="Add to Cart" name="WA_Store_Cart_1_ATC">
</form>
