Availability check of raw material during sale order processing

Dear experts,
                       When i am entering the finished good in sale order processing,system should check the raw material availabilty.Is it possible in STD sap


thanks to you all for your reply,
My customer is bright bar manufacturer,They just buy the steel bar & process it & sell it to the customer.So there is only one RAW MATERIAL.
Their all the activities are mainly based on raw material.So customer wants.....when we enter the finished good system should check the RM stock,based on RM STOCK,sytem should do the availability check...& confirm the delivery date
I have mapped customer requirement,after modifying item category & assignment......
Sales BOM explosion & delivery group is maintained for header material.availability check is on at component level & header level.So now system consider the raw material stock & it conform the dates when  i do availability check combinely.
I would like to know how it will affet the MRP incase of alternative BOM....FURTHER PROCESSING
Is it the right practise.....Please reply...............