Will I be able to get the Golden warring kingdoms chroma?

I do not have a definite answer on that specifically, but here's what I can tell you. The last I heard from Riot is that they have not decided to make the similar Gold Championship chromas limited to this event and they are discussing it. So that so far means that it is possible for them to come back. If you would like it, you should express that desire to Riot by telling them that you want past content and event content to be available to be acquired at later dates and later events.