Ive been looking on line-figure be a simple search. (Actually more on point using 'transition reducer'?) I'm amazed at how many different types there are. More so how many folks whose primary business is threshold, stair nosing etc. Closest to our has a rubber bulb on flat end door
Leaning toward making one since I would have to add to most or modify, generally max is 1" transition. Only issue is making it non slip-but it could be a bit longer since you end up standing/stepping on it. Could trim about half that frame lip off which would help-
Who would have thunk...
Scabbed ours together to use until I come up with something. Curious why our door is set so high.