My Bilco doors that lead to the basement leak at the top edge.

Other than replacing the doors, what can I do?

I Don't Think Bilco Is In Business Anymore, Well Tecniquely They Are But Depending On How Old That Door Is, They Want Have Any Replacements, Ive Delt With Them Here In The Last 6 Months On A French Door.

We Work On 100s Of Doors Every Year With All Types Of Problems, Send Me A Pic On Here Or Describe More In Detail Of The Type Door This Is , The Brick Mold Type , Is It A Metal Jamb, What Type Of Exterior This It Fastened To.
Any Info Like This Well Help Me Solve Your Issue

The doors are the metal jamb type and the exterior of the house is brick

Well First Try That Number, If They Can't Help , You Can't Still Get A Metal Door(prehung Unit) It Will Be Special Order, Since The Height On The Door Will Most Likely Be Undersized. A New Door Will Be Taller.
If You Go This Route You Can Have A Door Built To That Frame, You'll Need Brick To Brick Measuments And From The Header Or Brick Linel Down To The Concrete Floor.
As Far As Attaching This 3/4 Boards Will Be Screwed To The Inside Of The Brick To Give You Something To Nail To When You Install It.
As Far As Removing The Door Jamb, Use A Sawzaw And Cut It In The Middle And Pry It Out. You'll Be Left With Some Holes On The Concrete Floor From The Jamb Just Pour Those Holes Full, Most Of Which Will Be Covered Up By The New Door
Hope That Helps