That's hard to answer. It all depends on what you want the car to be, how much you're willing to spend, what work you can do yourself, what your future plans include, etc...
That appears to be an aftermarket 600CFM square bore Holley, which is an adequate carb for most small blocks. Going by the missing oil filler tube, I'm going to assume the engine (or maybe just the intake) isn't original so getting it back to a more stock configuration would include taking care of these things first. If the car started life as an L30 or an SS-350, it would make it a little more valuable installing the original intake and Rochester Q-Jet carb. However, if it started life as an LF7, then not so much.
Rebuilding Holley carbs is pretty straight forward and fairly easy, but I don't know what your capabilities are. The Q-Jet is also an easy carb to rebuild, so it's soup or nuts.
If you want it to "look" stock, go with the Q-Jet. If you never plan on removing the air cleaner, no one will notice so stick with the Holley.
Ultimately, it's your decision.
Ed