Lack of supply

Please help, ive been underactive Thyroid (Hashimoto) for 20 years was on Levothyroxine for 14 years. Felt awful, tired, hair loss, weight gain, Fibromyalgia. After reading up on NDT Started self medicating on it and immediately felt the benefits. I no longer felt tired, aches and pains subsided, my weight steadied and I was able to lose weight with a group. But now I'm running out of my NDT meds and cannot find a supplier anywhere that has it in stock. My GP has prescribed Levothyroxine and told me to take one of each to make my NDT last longer. I was taking 2 grains NDT. I don't want to go back to how it was but already I feel my body aching taking the synthetic meds. 😔