It's not that soldering is a poor way to repair the radiator. It just will not work. The aluminum core ends are crimped on the plastic end tanks of the radiator. Nothing is soldered.
If you want to order a radiator, call the company and give the the last 7 digits of you VIN. That should tell them exactly which radiator you need,
What is the mechanic going to do for $390? Does that include the price of the radiator?
2001 530i/5 S+P CDV delete/Akebono ceramic pads
M5 SSK/RedLine MTL/M5 rear sway bar/Bilstein HD
BMWCCA Member #337964