Replacing external box

[Bodgeitandleggit]

Hi, as soon as the weather gets a bit warmer I am painting the front of the house and going to smarten it up and with the external bell box looking a bit tired I am going to replace it...it is working fine but I want to replace it with the ones that have a light to show that it is active ...not sure what it is called by I have seen them where the light at the bottom of the box appears to be moving from side to side, will this req extra cabling or can it be done with the wiring in situ

 

[Alarm]

You should be okay with existing cable.
Most sounders run off 5 cores, yours should be the same.
Some 6, so you might have a spare, if your unlucky and its 4 core it can still be done but not as efficiently.