Best Infinity base for Javazon merc

My Javazon’s Act 2 merc has an Andy vis and Fortitude. What is the best possible base for an Infinity for this merc in terms of damage per second? I don’t want to change my armor or helm.

I don’t currently have a +15 IAS jewel in my Andy vis but I could add one if necessary.

eth Thresher 202020202

why does Eth thresher beat out Eth mancatcher if you dont mind? i’ve always seen speed as a massive damage multiplier and mancatcher is pretty fast