RetiredMil, I don't believe your sporterized Krag was modified to fake anybody out. It looks like an honest to goodness modification to suit a purpose years ago, likely for hunting. I don't know your situation, but anybody who tries to sell a sporterized Krag as an original carbine is either uneducated when it comes to Krags or is a fake himself.
Not sure what you paid, but you can still get some enjoyment out of your sporterized Krag learning its inner workings as you study a book like Poyer's as Butlersrangers suggests. You can shoot it (check it out first), reload for it, and show it to friends who likely never seen anything like it before. Then you can wait for the great deal on a carbine that you can ascertain for yourself that it is for real after you studied the Krag. Lots of good info in this forum if you go back and read earlier posts, also. Takes time to soak it all in, and when you think you know everything you need to know, somebody throws you a curve ball. All the same, it will be an enjoyable journey.