At left: The very common ULN2803; picture borrowed from Adafruit Industries, who sell them for $1.95 a pop.
The Harris Z16HD+ transmitter at work has a bunch of these STMicro L603C Darlington arrays all over in weird places where Harris decided to run things unnecessarily off the +50-60V PA power supplies.
Original part datasheet: L603C
The L603C’s max voltage is 90V.
The only replacement I have found so far that has a suitably high voltage rating: SG2823J. SG2800 series (SG2823)
At this point the question can be raised of “how much is that piece of equipment REALLY worth to you?”. If you need to replace an L603C that is used in a lower voltage application (voltages below 50V), the common, inexpensive ULN2803 is your chip! (See link above.) If you need that high voltage, though, prepare to open your wallet a bit wider than usual…