BK I'm glad you have been able to decide on a plan & that you feel you have other options if need be.
SueLW, I was thinking of Thyroid Binding Globulin (TBG) rather than SHBG. It's usually said that only oral oestradiol increases TBG meaning we will likely need an increase in thyroid meds. But several of us on here have found the same seems to apply to transdermal methods, which was my point to Blue Kingfisher. Sorry if that wasn't clear. And yes, agreed, it's usual to increase thyroid meds to accommodate HRT.
I'm so sorry you are one of the significant minority of patients who need T3 & can't get it prescribed. I'm another, but have been lucky to have the relatively recent support of a very good Endo consultant who knows I need T3 & kindly intervened on my behalf when it was withdrawn from NHS dispensing a couple of years ago. I have to see him privately though. Like you, though we are not that comfortably off, I now pay for my TFTs & other endocrine bloods as the NHS won't usually analyse anything other than TSH. I agree it's not right that if we fall into this subgroup we often have to advocate for ourselves. It can take so much time & mental effort to keep on pushing for the treatment we need, which I've also found really stressful over far too many years. Is it not possible for you to see an Endo who would prescribe the T3 you need? If you are known to have the conversion defect surely the need for it is clear, as it is with me?