Can I repair an ignition problem on a Moffat 3500 gas hob?

I have an ignition problem on an elderly Moffat 3500 gas hob. All burners work OK after 20 odd years but there is no longer any ignition spark when any of the burner controls are depressed. Power is on at the unit. Is this fixable these days given the age of the hob? I am trying to avoid purchasing a replacement as it would also entail changing the worktop since the hob is a non standard size.