How to add a private custom entity record which is only viewable by the owner but also allows the primary field to be searchable via a lookup for all users

I don't think I can use field level security here since the owner will be different on each record (btw we're on crm 2011)

I have thought about creating two custom entities - one that will allow read access set to 'organisation' with a lookup field to the corresponding private entity (with the private attributes)  that has read access set to 'user' and the owner set appropriately.  This first entity list will be used by general users to populate a lookup field on another unrelated entity.

This is workable since the data will be created via scribe but just wondering if there is a better way of doing this?

Thanks

David