Hello ,
I can see product is also having a range. From SRM 701 the ranges are available for lot fields which will be available with switch Range search in Sourcing Cockpit . If you are in SRM 700 then this functionality is not available. But having said custom developing it would include building a wdr_select_option with an appropriate structure which contains a range table and not a structure filed.
Hope this helps.
Thanks and Regards,
Veera