You have a Mod 1, but not limiting yourself to clone correct. Why? Get the NF 2.5-10x24 and enjoy it, and be clone correct. The other clone-correct option is not one you will want to consider, as it is great for period scopes, but you can do better.
I do think the NF 3.5-15x or the ATACR 4-16x are great choices if not concerned with period / clone correct. This is a 600m rifle, so go with a basic reticle. If you are an MOA guy, then the MOAR or similar NF reticle is a classic that will never go out of fashion. Clean, easy to read. Just pick F1 or 2nd FP.