Is this map still accurate?

Can we improve it, today? I assume we have more than 14 Pulsars we can reference, now, right?

How far into the past or future would this map be accurate?
I'm performing a private experiment, and being able to plot Earth's position from any point up to 7 billion years in the past or future from any vantage point in the observable universe is a keystone of what I am working on.