Harold Melvin
Mancunian Slang for a five pounds note. Dervived from the Soul Singer and his band - Harold Melvin & the Bluenotes. The reasoning being a five pound note is Blue.
1) Lend us a Harold til Friday. 
2) Tickets are only a Melvin each.
3) That Harold Melvin is Jeckle (& Hyde i.e. Snide)