Finest gold fan?

Firstly thankyou for the answers on my previous post.
My fan has now packed up on my Halstead finest Gold boiler, it tries to move but doesn't get going. It made a bit of a noise before stopping and refusing to start, luckily I heard this and switched off.
What i would like to know is can the motor be repaired? Do I have to buy the whole assembley? Where would be the cheapest place to buy and can you get 2nd hand motors/fans? Thankyou. :-)