Welcome to Pantera ownership. It’s hard to fix a previous owners missteps, but I’ve always thought one of the classic aspects for the Pantera is the pop-up headlights, often called frog eyes.
of course, many of us have upgraded to better and more modern headlight assemblies to replace the original 7 inch lamps But most Panteras still retain the original headlight assemblies
New fender tops, including the headlight bucket cut outs, are available from vendors here in the USA. In your case you could just use the forward portions of them to restore your fenders. No need to remove your entire fenders.
headlight buckets are somewhat difficult to find. They generally sell between 300 and $600 apiece.
this is assuming you are able to perform the metal work, and perhaps fabricate other missing portions by hand.
some more photos of exactly what you are dealing with in regards to missing sheet metal would be helpful for us to provide better informed advice.
The front of any car is it’s most recognizable image, and I believe I speak for many other owners in encouraging you to consider and investigate restoring the headlights to a stock configuration.
We are here to help, we just need the questions to answer.
Larry
P.S. - I have three or four headlight buckets in various conditions, should you decide to go and that direction.