With those high temps you’d be better off focusing on a shade structure than worrying about the details of pottery. It would be so hot for your trees that — even if they had “good” pots — they’d be putting almost all respiration efforts into staying cool rather than growing. At those temps you’d possibly want 50 percent shade cloth.
Even simple terracotta pots are generally compatible with those temps — the high and low. They aren’t fantastic, but their porosity helps to cool off with water evaporation.
I’m not specifically vouching for terracotta so much as trying to steer you to the bigger, more severe limitation in your climate.