Thanks for the responses guys - I got a combination bead and cove bit from Lee Valley as well - had a friend coming back from Canada stop in and pick me one up. Unfortunately, I have ended up with a 3/16 radius, when I was aiming for a 3/16 diameter!

I have a bottle of the Fullers Aliphatic PVA, so will probably use that in light of the earlier advice. My thoughts on thickening the glue were along the lines of making a batch of colourmatched glue, and using that to glue the strips. Once faired and sanded, any contamination of the surrounding grain would have been removed (most of it would be on the high spots along the joins), and there would be no gaps left to fill. Rob Mack outlines a straight forward looking beveling method on his shop tips page, so I think I'll try that, or a variation of, rather than trying to get another set of B&C bits shipped over at this point.

http://www.laughingloon.com/shoptips2.html

Now I need to hunt out some timber. It seems that commonly available (and cheap) pine when cut into 4.5mm thick strips will weigh the same as a 6mm WRC strip, and still be slightly stronger.