Only one. $40 local only (Sacramento, too heavy to ship). It appears the dust shield is symmetric and fits either side (P-P PN 126-421-02-20-MBZ).
I'm keeping the other for my two 300D cars. If you ever had a bearing spin in a hub to ruin it, you will appreciate a spare. Happened to me long ago on both fronts in my 1969 Dodge Dart. I would use the rotor with no concerns since measures 0.495" and has no wear ridge or waviness, vs 0.500" (12.7 mm) new and 0.417" is minimum (per Bendix PRT1387). I would clean and inspect the bearings, then re-use if quality brand (German). If you need new bearings, I recall the same PN's as 1970's GM pickup (A-3 outer, A-5 inner).