It doesn't matter!!!!
Suppression is precisely about forcing the SAMs to turn off their radars. An escort that has jammed the entire air corridor from Iran to the B-2 is safer than simply sending a lone B-2 to bomb a sensitive/critical facility in a not entirely permissive environment, where the chances of being shot down are much higher.
For SEAD/DEAD, they had:
Electronic warfare (EW):

G550 Shavit SIGINT/EW

EA-18G Growler (active jamming and radar suppression)
Standoff munitions:

Tomahawk (EW variant)

Delilah (precision standoff SEAD)

Rampage (supersonic standoff)

AGM-142 Have Nap
Kinetic delivery on target:

F-16 (AGM-88 HARM)

F/A-18E/F (HARM)

F-35I (Spice 1000/Delilah in direct SEAD roles after initial jamming)
It is worth noting that there are EW Tomahawk variants used in SEAD to be paired with real-time ISR (e.g. MQ-9, G550) to manage adaptive radar frequencies.
Also, I believe the MOP range is something like 5-10 km, considering the altitude it launches the GBU-57, but because of GPS/EM interference, I believe they advanced even closer to Fordow and Natanz to bomb the facilities.