Question for those who rebuild, not replace...

Planning my long delayed hydroboost installation. Just waiting for the coincidence of reasonable weather and available down time to arrive. Obtained the proper dual return PS pump along with the hydroboost unit from the donor truck. Since this will leave me with a spare PS pump, the plan is to rebuild both since they are already out of the truck. Primary that is currently working fine in there will go straight back in with the dual return shroud. My question is more about the one that would be rebuilt and placed in storage for Months/Years/Decades before it goes into service. Will PS fluid be OK for the O rings or would silicone grease (like that stuff for kitchen faucet o rings) be a better choice? Since this could be very long term storage the plan is to put the pump inside a food seal vacuum bag to minimize air contamination while lingering on the shelf. My concern is that PS fluid could become sludge or attack the rubber over time. Then again, would the silicone grease even if sparingly applied contaminate the PS fluid once it was placed in service? Thanks in advance for your thoughtful answers...

You could use assembly lube like is done with hydraulic pumps and motors, transmissions, etc. They can sit a LONG time before going into service. The oil used to fill the system will dissolve any residual assembly lube and not cause problems.

https://images.oreillyauto.com/parts/img/large/lbg/19250.jpg

Coolness
will stop by locale "real" auto parts on Monday to order some...