You can’t get them to apply. They are already very well paid. It’s a finite pool that is not large enough. Bidding up pay won’t change that. Instead you just hire overseas.
working with what tech? you didn't answer the question to a reasonable extent. it seems odd you need to hire people into principal and "distinguished" titles, you should be promoting from senior/staff to fill those internally. unicorn hunting is an organizational problem, not a useful reflection of the hiring market