Yes you can replace the neon indicator light in there.
Theres usually 2 ways to access this.
Either just the front control panel comes off.
Pull all the knobs off and open the doors and look under the front control panel.
Find the screws under there and remove them and see if the panel drops down so you can pull out and access the light.
If not then the hob top will need to be removed.
Pull the oven out and look at the back of the hob top on the under side and theres usually screws holding this at the back.
Remove them then lift the hob top up from the back and slide forward and the top will lift off giving you access to the front control panel and the light in there.
With that off you can replace the light. Its not just a bulb it will be a complete lamp with the wires on it its only 2 wires which will need to be rewired up. Once you have it off you will see.
So its quite a strip down to replace the light but it can be done. If you didn't want to go stripping it down yourself then getting an engineer in to do it I will say you are looking at roughly £50-60 fully fitted.
If you need anymore info just get back to me.