Well done.
Yes.
When I first read about 5" heels, I thought that starting off in a stiletto that high would be counter-productive, until I saw the shoe size of 44/45. (Counter-productive as in 'too hard' and might encourage failure.) With a size 10 foot, a 5" heel should might well be a challenge, but achievable for a determined wearer.
What to buy, and what not to buy?
Firstly, what not ....
Only yesterday I was in TKMaxx, trying on an attractive pair of Diesel strappy ankle boots. (Sorry, no piccies at the moment.) They were a size EU40/UK7 and had a zipper up the back. I don't usually get on with this position of fastener, so I was surprised I got the shoes on, but I did. While I have regular sized 8 feet in length, they are slender (ish) so I sometimes manage a large 7, which these were. They had (have) a 5" metal heel, which is what drew me to them. Mrs Freddy had tried them on first, and didn't want to try to walk in them, so despite me being a bit close to home, I tried them too.
They looked great on, had the upper end of my wearable heel height, but .... They were lethal. So unstable, I would reasonably expect to have a broken ankle on my first outing with them. I can only liken it to wearing a high heeled slipper and the heel tip was machined to a point. If I didn't move, the 'heel wobble' wasn't so bad, but even breathing induced movement. I've been wearing a heel for some time, and I couldn't wear them.
I would recommend Pleaser. They are stable, being designed for men to wear, and their range is quite large. They are no longer as inexpensive to buy in the UK as they used to be, and few outlets carry stock. (The exception might be Banana Shoes, who I also recommend.) The newer Pleaser style with the vertical heel are hard to walk in, so I would suggest one of the older (classic) styles with the curved (inclined) heel. There is some discussion on this board about heel-tip position that is pertinent regarding these styles, that might bear some reading if you are unfamiliar with it.
While you are into boots, getting the right size might take some work, so I suggest getting the sizing using shoes. Either ordering 2 or 3 sizes at a time, or hoping to get lucky and ordering what might seem like the right one will almost certainly involve returning products, and returning shoes is cheaper than returning boots. I am thinking (aloud) that faffing about with shoes to get the right size, could be easier/cheaper than faffing around with boots. Once you have the size, then you can order new or buy 'unused/unwanted' at a better price - possibly, in a style you prefer. Boots and shoes from the defunct Little Shoe Box (aka LSB), now "Leatherworks" or Burlesque Blue, will all be strong enough to support a 6ft man. I believe Burlesque Blue (and maybe Leatherworks) still offer a made-to-measure service if you have that sort of inclination. There are other people offshore who might do the same or similar thing for a bit less money, but the makers I mentioned are in the UK where you might get the benefit of some face-to-face advice if your interest progresses.
Often resellers/retailers will recommend going up a size if wearing a heel. I have never found this good advice for myself. In fact with a court shoe, I've found the opposite to be true. When I put on a size 8 court, it fits. When I've been wearing it for 10 minutes (and my feet have reshaped themselves) my foot falls out of the shoe. Wide feet might get some benefit from a larger shoe, but I don't have wide feet (thankfully).
All that said, there is at least one 'local' heel enthusiast around your size who is a member here. It may be you could meet up for a 'trial' that would be no more expensive than the cost of travel to a mutually convenient venue. There are more active members on HHP, and maybe you've already had a similar offer from one or two there?