Issue related to planning products for textile industry

Hi All,

We are from textile industry in india. we are using SAP and now for us planning is big challange. we are into make to order.

Please fine the one Example.

suppose we create SALES ORDER for example 500Kg yarn etc

Lot size is kept open (lot for lot) and the demand can vary from like 1kg to any number depending on the nature of the order / size

Resource selection has to vary depending on demand qty is the business requirement

Example: WC1 : 600kg / day

WC2 : 900kg / day

WCn 1000kg/ day

And like that there are about 300 WC on which the order can go; based on availability of the resource.

Question is how to select the resource whose capacity closest matches to the demand qty?

Example for demand = 100 kg and if WCx is 100kg/ day and available i would want the PP/DS planning run to select the same dynamically.