Hi SatNav........
Yup -
Decathlon seem to have the identical 'Prowheel' chainset in their inventory at a reasonable cost.
I (personally) wouldn't overthink the crank length. My 54" Triban came with 170mm cranks......my MTB has 172.5 cranks and my old Mercian Tourer had 175mm cranks.
I'd be lying if I told you the difference had ever worried me!...........HOWEVER..............your mileage may vary? I'm sure that a lot of experienced types CAN tell the difference-and I know YOU are experienced (!)........so pay no attention to me!