No perlite...

Cant find perlite around my country but i found some round rocks really small i would say perlite size... can this work?? Without afecting something? Ofc i will prev put em in the oven

Perlite is sold as insulation too so chech those sources. I've never used gravel..sorry. Can you get pumice?

Get a bag online. Like ebay or something. They're cheap

Or use styrofoam packaging material maybe. Tear them up and through them in the soil.

Try this.............
http://www.ebay.com/sch/i.html?_nkw=perlite&_sacat=2032&_odkw=&_osacat=2032

Perlite is important because it absorbs water and makes that water available to the plant instead of just running out the bottom.
Any good organic soil with 10-20% perlite is what I use. Miracle-Gro Potting Mix works for me.

BigSteve.