Looks like a zinnia, one with a single row of petals (doubles are more common).

I see you live in the UK. I don't know where "abroad" you saw it, but in the U.S. zinnia seed is commonly sold by vendors who sell seeds of annual flowers.

ZInnia seed is widely available in the UK but our lack of hot summer sunshine means they are not always reliably successful.

Here is a link that might be useful: Zinnias