Clothes dryer vent exterior wall

Where to buy. Mine is toast.

I would start with your local hardware store, then Tool Town in Ajijic. If nada then Amazon.....

https://www.amazon.com.mx/NuTone-WVK2A-Flexible-Ducting-Ventilation/dp/B0019XXOMI/ref=sr_1_3?crid=1PMUQD8NKEVIL&keywords=dryer+vent+kit&qid=1700586648&sprefix=dryer+vent%2Caps%2C124&sr=8-3&ufe=app_do%3Aamzn1.fos.4e545b5e-1d45-498b-8193-a253464ffa47

I am unsure if the OP is talking about the actual duct hose or the part with louvers that sits in the outside wall to which the duct hose attaches. Both are available at the majority of ferreterias locally.

The title talked about an 'exterior wall'...

Yes the exterior louvers attached outside. My louvers fell apart. Dry rotted.

Tool town didn’t have one. I’ll try other places

Just a suggestion to ask for what you want if you don't see it.

We did in Spanish and I had the old one with me. I’ll find one at a hardware store.