http://www.noahsark-naxuan.com/arkmodel.htm
Extract from the above
"Gopher wood" is a misreading and scribal error. "Kopher" wood is correct and means wood (any wood) that is covered with Kopher. Kopher is bitumen. In the Genesis text (6:14), the context is clear. The GPR wood used, (a scribal error) is to be covered in KPR. G and K in Hebrew are so similar that inexperienced Hebrew "scholars," such as those translating the King James Version of the Bible, could have been prone to such errors, indeed, they made many such errors.
IF this is correct, then it could be any wood available in the area,IMO