Errr... Clockwork Orange? Happy to explain it, but if you're reading the book you'll really need to re-consider English vocabulary from the ground up. But here goes:
"Can you spare some ______, me brothers?" Look at it logically: whatever he is asking for, my first guess is it has to be either spare change or food.
He actually means spare change, also known in Cockney slang as "rifle" ("rifle range"). "Shrapnel" is another common slang for coins. Specifically, a "cutter" was a 10 pence coin. Apparently these were easy to sharpen and use as a tiny blade by prisoners.
"Blerp blerp" you could guess by the sound. ;) I guess either the 'filthy old drunky' was either burping or vomiting while he sang.