Robin,

You can also get the flush plugs for rails mounting from the front and SBC rail might offer a few different options, then there is going over to traceparts and looking up the French/Swiss rails (not much different in price from Hiwin from what I have seen) and seeing what they offer as well. I need to look up th Italian firm that sells different types of rail on the per project basis as most want you to buy way to much. Good luck

Michael