Rebuild symbols

I accidentally deleted the original program. 

I backed up the program from the CPU but I no longer have the symbols. 
From an old version of the program I retrieved the symbol table 
(variables and names of DBs, FBs, FCs, GRAPHs). 

Is it possible to retrieve the names of the internal variables of FBs, 
DBs and GRAPHs from the old version of the program?

Thanks​