I keep two varieties of grease on hand for mechbox work.
The G&P grease set seen here
Which includes Bearings/bushings grease, Cylinder grease and Gear grease .
And I also keep some Guarder teflon grease on hand.
as seen here.
Its a decent simple goob for general mechbox use.
For actual silicone oil, I keep a bottle of AI light weight silicone oil and some unknown can of Japanese spray silicone lubricant amade for airsoft guns.