Hi,
From the diagram I was able to make out that you need a 3 level category listing. Ideally, this can be done in a matter of minutes using jQuery. However since it is placed on top of the code you already have, I would need to see that in order to say the exact time, which maybe from a few minutes to an hour or two.
Do consider the bid and we can get it done asap.
Regards,
Arun