OK, what is your input voltage range? I tried using my crystal ball with the numbers that you did provide and I guessed wrong. If it is not 5-125V then were those numbers given as a diversion? And now, you mention 450V. Is that related to the device that you're seeking?
And what is your output current? I guessed 1A which obviously is wrong because now you say 20mA. Maybe it is some other number. Enlighten us.
When looking for a LDO regulator, the input voltage range and maximum current are paramount. You have given many numbers, none of which are useful. Do you not know how to define a regulator?
[edit - I see your title says you want 5-100Vin, 1A out, which means that it would be a whopping 5% efficient instead of the 4% that I said earlier, and would only dissipate 95 watts. I regret the error.]
The part that you need may very well exist but you won't find it by providing random numbers that are not related to your requirement.