I used the tabernacle to mount blocks - with tufgel (sp) as a lubricate to keep the SS screws from seizing.  I'm sure that a custom plate could be made to attach to the mounting bolts for the tabernacle but at a $$$.  
You could call LaFiele and ask... 
In 2005 I worked with Don Averill (562) 921-3411 ext. 330 to purchase the new mast.
HTH
Jay