As I mentioned in an earlier comment from the free SPS who aren't used for the liquidy pools.

In this document stand 7.5 million SPS but only 5.25 million SPS seems to be allocated:

https://docs.splinterlands.com/splintershards-sps/providing-liquidity-sps

Roughly 500k SPS (from the free 2.25 million SPS) would be enough to replace all leaderboard-prices with an equal amount of SPS on base of the actual rate from roughly 30 DEC = 1 SPS.