So got the transistor. I ended up buying BC807-25 instead of BC808-25 (they have alomost identical data) as it was easier to come by.
desoldered the old TR13 with hot air, and soldered in the new one.
Testing and red light turns on in the IR eye. Meassuring with multimeter shows 5.46V so very close to the specified 5.5V.
So now I just need one Bench supply for it until I find a 15V power brick.
unfortnuatly the ribbon cable to the PL connectors broke of in the proces so need some extra repair work before its ready for further testing