Function moduel for finding open offers

Hello togehter,

I search a "standard" function module to find all open offers for a customer and a article.

This means:

During order creation with BAPI I have to find out if a open offer exists for a customer and article of position.

Open means valid date and quantity which is not blocked or already delivered.

Do anybody know a function module where can deliver this informations?

I have debugged the VA01 but I found only some subroutines which select the offers and contracts.

I am not sure if I am the first one with the need of this functionallity.

Regards

Christian