Veteran gear to convert in the Catalyst is also farmable. If you have excess Valorstones, you can just dump it on boxes for random M+ Veteran items if you have the 1200 rating or w/e that’s required to unlock it. And you can use Undercoin to buy specific slots from the delve vendor. Between the two, there’s no reason you couldn’t reliably finish the LFR set, and use Catalyst charges even now that you may not need for anything (even if they’ll become free/infinite when the season ends).