stelrad Ideal W gas boiler manual ?

I have a Stelrad Ideal w gas boiler - when i try to ignite the pilot i can see a spark from the igniter but it is not igniting the gas flame and the ceramic insulator around the ignitor electrode appears to be broken.
can the ignitor be replaced?
The boiler is circa 1982- are spares still available?
If yes - where can i get them?
Is a manual with spare parts list available?