Manufacturers only make things that they can sell. If they made a 58" tub they might only sell one, and that would be to your. If you cannot use a 60" tub, the next smaller commercial one is 54". Anything between the two measurements would have to be plastic and made locally. After this you can try Here is a link that might be useful: Walk in Bathtubs

My grandma eats sweets including homemade pies with 1-2 c sugar per pie, loves sweets in general, eats too many fried foods for my taste, doesn’t eat paint chips, bathes in a porcelain tub, and was JUST moved to a nursing facility this year since she’s losing her mobility (mind is still intact) and in another month she will be celebrating her 100th birthday. You don’t have to live in a bubble to live a long life. Much of your life expectancy is predetermined in large part by genetics. Use common sense and don’t lick the bathtub.

Have you been to the HydroSystem web site? That's the tub our builder is recommending. They have a lot of options, although I'm not sure what would fit in your space - I assume the tub has to be somewhat smaller than your alcove, right? The 40.5 inch measurement seems to be somewhat small for most tubs. The "Carli" there is 60 inches by 36 inches and holds 45 gallons, maybe that would work for you? Here is a link that might be useful: HydroSystem Tub overview

"I could also just get a pull-down faucet for the sink and aim it at the tub to fill it." You could - but you won't like it. The most one of those will fill is 2.2 gallons a minute - some less that that. Divide your tub's capacity by that and you're looking at 20 minutes to fill +/- Not good. beekeeper - I have one of these and have placed more than half a dozen in projects over the past few years. What you get for your money is a machined brass body that mounts in the ceiling or wall and a plated trim piece. The body is a substantial piece of hardware and chrome,brass, nickel plating costs $$$ too. Whether that's all worth 500 + bucks, is up to you. Like davidro says, it doesn't matter what the delivery system is, this is just an opening for hot water to come out of, albeit one with a bit of engineering. GD & Spanish - the splashing is very much dependent on the mounting height of the unit AND the tub selected AND the location of the water column inside the tub. Mine hardly splashes at all. The ones I have seen that splash only do so for a minute or so until their is enough of a pool in the tub to counteract it. Flat bottom tubs with tall ceilings are going to splash more than one from 7' into a sloped contact point in the tub. Besides , we're talking water in a bathroom, generally tiled so what's the big deal ??? It's not like the amount of splash is the same as taking a shower and leaving the door open. 2. While you are correct in that "the water cools off much more than it would from just a regular tub filler", it's not as if it cools off enough for anyone without a thermometer to tell a difference, and a very sensitive one at that! Sure the air cools the water more from a stream falling from 8 feet than one falling from two feet. But bath water that is 100 + degrees is not going to cool down to 90 deg. in the xtra 1-2 seconds it takes it to fall from the ceiling- get real. Additionally , that filler produces a very dense column of water (laminar) that has little to no air in it, so one might argue it will be hotter and less prone to heat loss than a "regular" filler that introduces room temp air into it's stream - thus cooling it off on it's way to the tub. So don't worry Spanish -your tub will still be plenty hot with that filler if you choose it. IT'S A NON -ISSUE people. I've already alluded to the real issue for lower tub temps - FILL TIME. That's directly related to the delivery system ( valve). If your valve and accompanying filler will only deliver 5 gallons a minute it's going to take a while to fill an 80 gallon tub, and there will be some heat loss. Select a valve that delivers 20 gallons a minute and you can be soaking quicker that most people can undress. Here is a link that might be useful: laminar valve body - see page 2