Soundproof windows or shutters?

Hello,

we have windows from 1992 without roller shutters throughout the entire house. Now, in the upper floor (bedroom), the street about 150m away is still somewhat too loud in the morning. The noise definitely comes from the window. Otherwise, they actually make a good impression, no drafts, etc.

Now the question arises:

1) Keep the windows and have exterior roller shutters installed? 2) Buy new windows and save on the roller shutters?

Which is better to keep the noise out? Which option is more expensive?

If the windows are not yet broken, I would use roller shutters, as they can completely darken the house and have burglar-resistant effects.

Are there exterior roller shutters that have at least 10cm distance to the glass (minimum requirement for sound insulation)? On the upper floor, there is no more clinker, meaning the window is almost flush with the (wood) facade....

What is better to keep the sound outside?

Windows, because they also keep the sound outside when the shutters are open.

Which option is more expensive?

Hm, I guess windows (if you install shutters at the same time as new windows ... ).