[ic] Offering Product “optional” option s or sub_items?

[sales at winecountryjewelry.com]

I’ve been using Interchange for about two years (now on 5.2) and am trying to 
modify my flypage to offer “related” product options, i.e. gift box, 
related “optional accessories”, add-ons, etc.

These “optional options” are not directly related to the parent item (i.e. 
size or color) and would be separate line entries, but as a related or sub-
item, would be removed automatically if the customer deleted the parent item 
from the cart.

I guess I am looking for a cross-sell/simple option feature which can be used 
to offer “sub-items” for a particular item or group i.e offer a Gift Box for 
SKU os001 but not SKU os002.

I’ve looked through the archives and haven’t been able to find an answer.  

Any tips or suggestions on how best to implement this would be greatly 
appreciated.