Is the door size no longer standard? Did I measure wrong?

Hello

I want to replace a door. The largest dimensions are 86x195.5 cm (so outer dimensions). According to the website, such doors are apparently not available at the hardware store. They only start at 88...

Did I measure incorrectly? That can't be if I already took the largest dimension...
I don't want to drive to the hardware store just to find out they don't have anything, so maybe go straight to a specialist store in the hope that I can get a suitable one there right away.
The door can no longer be closed, so it needs to be done quickly.

I also want to improve sound insulation and thermal insulation to the stairwell at the same time.
The security the door provides is "irrelevant" to me, so not important.
Since it's an apartment door, the appearance is initially "secondary," although it should also be wood.

How many euros should one roughly invest in a good door?
I would be interested in a rough guideline.
Incl. lock, hinges I have.

Well, then you have to buy the frame as well. Unfortunately, we also had to find out that the hinges do not meet the standard.

I imagine it to be difficult since the frame is a steel frame that cannot just be removed from the masonry. This also does not make the possible size any bigger. It probably can’t be smaller than my current door either.

Best to go to a professional, from here your door cannot be measured (door leaf outer dimension).

Take old door leaf with you …

So if the door leaf has a widest measurement of 86cm, then this is a completely normal standard door, or am I mistaken? These are, for example, in Herholz doors usually 860x1985 mm. Or what measurement do these 860mm indicate for you? If this is the width of the door leaf, then this is a standard size and I don't know what you were looking at in Bauhaus. ;-)