I don't think the NIST database will have Rydberg states. It's a bit exotic.
I am confident that the information you want can be gleaned from this paper out of Bob Field's group. However, this stuff makes my head hurt. All I know is that the dipole moment is proportional to the slope of a plot of Stark shift splittings vs applied electric field. How that depends on the angular quantum numbers is where I get lost. @EigenState137@amoforum@DrDu@BillKet are all people who are more comfortable than I am with this stuff.