I looked into this a couple of months ago and concluded that the BD809
(NPN), BD820 (PNP), MJE2955T (PNP), MJE3055T (NPN), TIP33C (NPN), and
TIP34C (PNP) would be readily available acceptable substitutes in
roughly that order.
Just be careful of the pinouts. The Tektronix TO-127 parts are ECB
while the TO-220AB and TO-247 parts listed above are BCE.
What about BD911/BD912 selected for a minimum Hfe higher than the
datasheet minimum? I used them without problem if I remember well.