(04 Jun 2015, 8:49 pm)Tom wrote The 43 often has ALX400's on, aswell as the 52/53 branded ALX300's. You could also try the 52 which should have an ALX300 on, but this is a longer route via Killingworth.
The X5 could have a Commander on, but if more often than enough a Gemini.
Not worth trying to bargain on ALX300s being allocated to services 52/53 though, really, is it?
More often than not, Pulsars are allocated, with the B10BLEs deployed elsewhere (especially on Saturdays, seemingly).