Hi Mr. Prasad,
Here are my two cents!
It is not that you are not getting any resolution at all. It is just that it is more complicated than what it might seem to be. A potential robust solution just might need involvement and buy in from MM & FI which may not be difficult given the clarity of the requirement now.
When we deal with ERP like SAP and requirements like what you have[non standard] the solutions cannot be looked at in silos. It might be the process flow which has to go through different modules to get to the desired state of good solutioning.
The questions the other contributors to this post have asked and likely paths which they were trying to propose[so that it could lead to a potential solution], looks to me, have been sincere.
Once we get an understanding of the whole picture [which for sure involves inputs from MM & FI] the solution would be possible.
It is easy to give up if we dont have the whole picture but we as SAP Professionals we dont give up for creative solutions. Do we ? 
That is our job to challenge ourselves to make ways for business to perform better 
Remember the SAP mantra -> The Best-Run Businesses Run SAP
Anyways, your choice!
Thanks.