I would suggest practicing with tubes then lugs. Much like practice brazing is often done. Get some tubing in (as example) 1.125"x .035 and some 1.25"x.058. The .058 walled tube will slide over the smaller diameter tube with about the right clearance for flow brazing. Cut a length of larger diameter, carve whatever you want and slide over the smaller and braze away. Far cheaper then using lugs.

When you're ready to move on consider lug blanks. Contact Doug Fattic and see if he still has the Nikko blanks he has stocked. Andy.