Hello from England. I must say how interesting it is to see the excitement over good old cockney rhyming slang.

What you have to remember, though, is that it's
slang.
So you don't say "He went up the apples and pears", you say, "He went up the apples". It's slang. Outsiders shouldn't be able to understand it.
Take a look at
Lock, Stock and Two Smoking Barrels for a good example of rhyming slang taken to extremes.
And, in the spirit of the rest of the suggestions, some more stolen from various sources, none of which I shall properly credit:
"Well spin my nipple nuts and send me to alaska!"
"Slap my face and call me Susan!"
...hmmm...
"By [appropriate dwarven diety]'s hammer!"
"Great [famous historical figure]'s ghost!"