Soy free protein powder?

I've been trying to find a soy free protein powder to use in the morning instead of eating breakfast. I take synthroid (225mcg a day) and I have to wait at least 30 minutes to eat. I usually take it when I get up and then get ready for work. I work almost an hour from where I live, so I try to eat when I get to work. The problem is I work at a bank, so once I get there and get the branch ready to open and start night deposits, I don't have a chance to eat. I tried eating between customers but that rarely happens. I would like to just drink a protein shake on my way to work and continue my normal diet. The reason I want soy free is I had thyroid cancer 2 years ago and had a total thyroidectomy, but a small part od the gland was left since it was so close to the nerve. Soy can affect those cancer cells (I drank soy milk for the last 4 years since I'm lactose intolerant) and since there is a small part of the thyroid there, I avoid soy whenever I can, in case the cancer cells would come back. (Soy speeds the cancer cells up making the tumor I had bigger) I can't seem to find a soy free protein powder..so any help in the right direction would be great! Thanks!