Ed and Penis Pump

Hi guys. For whatever reason I have some difficulty with erections and I’m finally saying enough is enough and I’m going to war on this issue. Viagra and cialis don’t do crap for it, so maybe I have some sort of mental block. I’m gonna try to penis pump and was wondering if any one of them off Amazon will be ok or should I go with a medically approved device? Any input or even different strategies are welcome. I’m open ears.