That can be confusing. Exceptions were made for "Original Covers" modified to fit the UGC cases as these are the only commercially available sleeve type cases that fit these older games.
Are you printing on cardboard and folding replacement boxes? I considered investigating that at one point but the UGC are pretty sturdy and keep the games safer. In these cases "Original Cover" has come to designate that it attempts to recreate the original cover in a new form factor as opposed to a custom cover which might use completely different artwork etc.
Antony30bc