Any of the dowel makers will have them, but they have not been sorted, spined, matched ect... but you can get bulk shafts at a fraction of the cost if you have a means to spine and weight match them. Atlas Dowel had them the cheapest by far if I can remember, but stock will be running out fast. Ramin is a twin of Mahogany, but has always been sold as a bulk junk wood in the US. Because of this, vast forests of Ramin trees have been wiped out, and has since been put on a threatened species list, and will no longer be imported into the United States.