Hardwood species timber widths

Hi all,
I am trying to find some type of hardwood 300 or 250mm wide so i can join two together to get a 500 or 600mm width. Would prefer a dressed timber. I have been searching for a couple of days but cant seem to find anywhere that can supply such a thing. I wouldn't of thought it would be so difficult as benchtops and tables are often made of these widths joined?

Any one know where I can source such stuff please?

Oh, and for those that are going to comment that speakers should not be build of hardwood, I know but I am working around that.

Thanks
Tony.