Yes there is a way to make a new door skin... but it ain't pretty.
1. Drill out all the spot welds around the door frame.
2. Cut the door skin about 3" below the sill.
3. Remove the skill
4. Obtain some 21 -22 ga sheet metal.
5. Drill/punch two 1/8" holes through the door frame lip and OEM door skin remains.
6. Slip the sheet metal up UNDER the OEM door skin remains.
7. Spot weld throgh the door frame lip to the new metal to hold it in place.
8. Clamp the new and OEM skin to getether and spot weld through the OEM door skin to the new metal.
9. Seam weld the OEM and new metal.
10 Using metal shears trim the new metal 1/3" around the door frame lip.
11. Drill/Punch 1/8" holes every 2" around the remaining metal.
Bend the new metal around the door frame lip and clamp to the lip.
12. Rivet weld through the 1/8" holes to the door frame lip.
13. Remove the clamps.
14. Grind down all welds.
I did this and it cost less than 15 for the metal. If you provide a cardboard template for the metal most shops will even plasma cut it for you.
See, easy as pie!