I haven't found a local that sells filters yet. Not that I've tried. This past week after running out of unused filters I used the same one a few times a day. It doesn't tear when rinsed under water or drying. The coffee filters through just like with an unused filter.
So if you're in a pinch just reuse the last one.
I've only used an aeropress at my friends place I was house sitting in London. When I ran out of filters I went and bought him (me) a Bialetti percolator.
Elegant solution. I'd probably buy a moka pot if I was starting out but we're just used to the aeropress now. Kinda funny how that happens.