RE: D&B Buckeye
KP.
Still flying my T-2 Buckeye MW54. (Search for the thread). Your best bet for a second tip tank would probably be to call Aeroloft in Mesa AZ. They recently supplied me with a spare canopy. Otherwise, could make a mold or even a styrofoam copy of the one tank you have and glass it. I have the plan sheets & could help that way, as well as details on a strong wing build and the Fuse ducting/ turbine mounting I used.
Email me. It's a great flying bird.
Cheers,
Larry Turner