I relate. However, I block on the word "Specialist" in my job title so every encounter where I have to introduce myself at work is a struggle! Here's something that might be helpful - I just found out about tapping today and it seems pretty promising just from practicing with myself. Essentially you tap a steady rhythm on your wrist or other body part and speak in rhythm to that. It seems to provide my brain a different stimuli that makes speaking feel less intense and also provides a cadence for words to flow to. In the past, I had developed a habit of stomping my foot to get past a word block but this is disruptive when I'm speaking on a stage or stomp a little too loud. Tapping so far seems promising. I'm going to try it in a work meeting and see how it goes.