Cacher is the code snippet organizer for pro developers

in transformation

add
<%@ Register Src="~/CMSModules/Ecommerce/Controls/ProductOptions/Ecobud_ShoppingCartItemSelector.ascx" TagName="CartItemSelector" TagPrefix="cms" %>
to the top

and 

<cms:CartItemSelector ID="cartItemSelector" runat="server"
SKUID='<%# ValidationHelper.GetInteger(Eval("SKUID"), 0) %>'
SKUEnabled='<%# ValidationHelper.GetBoolean(Eval("SKUEnabled"), false) %>'
ShowProductOptions="true"
ShowUnitsTextBox="true"
AddToCartLinkText="Add to cart" />

note: ~/CMSModules/Ecommerce/Controls/ProductOptions/Ecobud_ShoppingCartItemSelector.ascx is kentico buildin code, make a copy before change it
ShowUnitsTextBox="true" will show quantity box and I could change its style in Ecobud_ShoppingCartItemSelector.ascx

* input box can only input number
onkeypress='return event.charCode >= 48 && event.charCode <= 57'