Not a professional opinion but if this is the first time it's seeing -30 oil I'd change it to 10W-40 or 20W-50 today. If it's had -30 for a while now I'd be less concerned.

Oil pressure above 1 bar at idle is fine. Rule-of-thumb minimum is 1 bar per 1000 rpm. You'd probably be concerned enough to have it checked before it got to that point.

Sixto
93 300SD