Front pads last anywere from 30 to 70 kms, depending on your driving style.
Front disks need to be changed when they reach the minimum thickness of 21.5mm (out of 24). if yours are close to 21.5mm, then it makes sense changing them now, so you don't wear them out excessively and risk warping, brake judder, or even cracking way before these new pads wear out.
If you do need new discs, you can use these oe numbers to find compatible discks
MITSUBISHI
4605A068
M4605A068
SMART
45442000101
4544200001
HYUNDAI
51712M2000
KIA
51712M2000
MITSUBISHI
MB928994
MR475330
MB668107
MR389722
MB407639
MR205585
MR205584
MR128153
MB928995
MR955637
PROTON
PW820577
VOLVO
308729268
30872926
You are looking for 256mm in diameter, 4x114.3 stud pattern and 69mm center bore. Carisma and S/V40 <2004 with modest engines have these same 256 discs, while higher powered versions have 282mm discs up front, just like the brabus. They also have 260mm rear brakes on these powerful models, compared to our 250mm ones found on normal and brabus forfours.