Given how lightly the blade brakes are used, never going downhill on the I-55 with a trailer full of firewood... They should last a long time and the glue used likely does not have to be rated for high temperature.
I would get some epoxy or some filled-epoxy such as JB Weld and use that. Make sure the metal surface has some 'grit' to it and is not polished shiny smooth so the glue has something to adhere to. I would apply using clamps to hold the pads to the brake arms. If you don't have clamps, get an assortment of rubber bands, and use as many as you think necessary. As long as the pads are held against the arm surface reasonably, the glue will set up and likely hold them just fine. This is not a high-temperature heavy-duty application. The heat generated is nothing like that of a truck or car brake system. The pads are applied for very few seconds compared to vehicle brakes, and at long separated intervals.
tom