Bonjour Kay,
In this particular text, you can use 'voudrais / aimerais' interchangeably.
Yet, you can't always use them interchangeably. There is a difference - see below:
Je voudrais un ordinateur = I would like a computer
Je voudrais devenir pilote d'hélicoptère = I would like to become a helicopter pilot
-> notion of will / decideness / concrete idea
J'aimerais un ordinateur = I would like a computer
J'aimerais devenir pilote d'hélicoptère = I would like to become a helicopter pilot
-> notion of dream / desire / hope
I hope this is helpful.
Bonne journée !