What does it take for an endocrinologist to decide if armour is suitable for subclinical hypo- thyroidism? If test results are all in "normal" range.

Subclinical hypo. Subclinical hypothyroidism occurs when peripheral thyroid hormone levels are within normal reference laboratory range but serum thyroid-stimulating hormone (TSH) levels are mildly elevated. If all test results are normal then it does not sound like subclinical hypothyroidism.
He/she will not. Armour brand dessicated thyroid is no longer the first choice of real thyroidologists to treat hypothyroidism. Be weary of anyone foisting it on you. See a real thyroidologist to find out if you really need any replacement for subclinical hypothyroidism.