I'm gathering bits to make a sliding door for a shed, and want to put a 6m length of stainless T bar on the floor as a guide. I'm looking for about 30mm x 30mm x 4-5mm thick so I can fix it upside down to the floor in a cast concrete channel.

I done a fair bit of searching online and it seems nothing is available in NZ. Most options seem to be china, India or the US. 

This seems unbelievable. Does anyone out there know if I can buy this in NZ?