EBC disks are very verys soft, and wear out super fast. If you have grooved ones, they won't be grooved for long.
I'm not a fan of EBC pads either after bad personal experience, but the Blue's seem better than the others. Greens and Reds are nothing more than paperweights
Lines are worth doing, as long as you get ones that are full stainless (I avoid goodridge as they rust like hell) then there's very little between the brands. I sell HEL lines as I like them.
My recomendation would be Mintex 1155s, Pagid disks and HEL lines, with ATE super blue racing fluid.
If you are only doing the odd track day then I doubt you need to change the discs. A lot of people like to change bits on their cars when its not necessary. Spending money on the cars is their hobby. I'm not knocking it, it's just I have someone always asking me if it is really necessary and making me think twice.
Having said that you will need some decent front pads. I made the mistake of doing a track day on motor factor pads and destroyed the front pads and front discs ( pads were down to bare metal) in one day. I switched to EBC yellow stuff on the front and they are wearing well after a couple of track days. The motor factor rear pads are hardly touched so don't waste your money upgrading those. By the way I believe blue stuff are for race use only. I have a friend who runs top running drivers in a Mazda MX5 race team and they seem get good results on yellow stuff.
For the odd track day you don't need braided hoses but I would suggest you change your brake fluid as it will boil and you will lose pedal feel. I just changed to motor factor 5.1 and that works fine for me.
Until you are extracting the maximum from your driving you are unlikely to need a lot of expensive brake upgrades. Yellow stuff pads and a brake fluid change will see you through fine for now with change from £100.
How much would this cost and is it really necessary for one's first track day?
you work for ECP, fit all Pagid disks and pads, they're utterly excellent, I fit loads of them and have tracked several cars with them on now.
New fluid would be ideal too.
Not changing disks when you fit new pads is wasting your own time
Really? How come?