You can use by-products and substitute parts. Co-products are not available in IFS (even though the by-products supports some scenarios typically covered by co-products functionality)

• By-products are additional parts produced in addition to the lot size of the main product. You can connect the operation on which this output is expected. You can also show this as a supply in MRP. The cost of the manufacturing and material can be distributed % wise among the main and by-products using the by-product cost distribution using logic.
• Substitute Parts. Cannot be planned in advance, but on the shop order you can make a receipt of a substitute part  (any part with same traceability settings I think) which basically says you receive this instead of the main part. So this decreases the remaining quantity of the main part.

Thankyou for the swift response. I will hand this to someone who knows our IFS better to see what would be the better course of action, but I think the by products would look ok.

Thanks

As clearly mentioned by Björn Hultgren. 

Yes this is possible to receive multiple parts through a single shop order (production order in other systems).

You could define the main product and other products in the by-products tab. Additionally by-product costing can be done separately.

Example many fish exporting companies have similar needs where some of the offcuts are defined as by-products and used for other processes.