What options do Mercedes have in the F1 driver market?

TL;DR:

• Carlos Sainz, though sources say Aston Martin, Sauber, Alpine and Williams are potential teams where he could land
• Alex Albon
• Fernando Alonso, if he ever get lured from Aston
• Daniel Ricciardo
• Esteban Ocon, whom is managed by Toto Wolff