From Word Play: A cornucopia of puns, anagrams and other contortions and other curiosities of the English Language by Gyles Brandreth (London: Hodder & Stoughton, 2015), page 229:


COCKNEY ALPHABET

A for ‘orses (hay for horses)
B for mutton (beef or mutton)
C for miles (see for miles)
D for ential (differential)
E for brick (heave a brick)
F for vescence (effervescence)
G for get it (Gee! Forget it!)
H for bless you (aishfa – a sneeze)
I for the engine (Ivor the engine)
J for oranges (Jaffa oranges)
K for restaurant (cafe or restaurant)
L for leather (hell for leather)
M for sis (emphasis)
N for lope (envelope)
O for the wings of a dove (song title)
P for relief (self-explanatory)
Q for the bus (queue for the bus)
R for mo (half a moment)
S for you (it’s for you)
T for two (tea for two)
U for me (you for me)
V for la France (vive la France!)
W for a bet (double you for a bet)
X for breakfast (eggs for breakfast)
Y for husband (wife or husband)
Z for wind (zephyr wind)