Not familiar with those roof bars but checking that part number and googling around a bit.-
I'm not clear why you refer to it as a Torque socket, did you mean Torx? either way it's not Torx it's a triangular headed bolt, ebay does have some
triangular sockets set of 5 for a third of the price.
I apppreciate people want to be sure their roof bars are secure against theft hence the use of an unconventional bolt head, but when anyone can go online and buy a tool it becomes pointless, if it were me I'd get the ebay sockets, remove the weird triangular headed bolts and replace them with something more normal which you can get a decent quality tool/key for, when I swapped the roof rails onto my V70 I ditched the rusted Volvo bolts and bought stainless steel button head socket screws from ebay, if I ever need to change them it's just a regular allen key.