If Ipswich is an authorized dealer, I'm sure it is legit. Doubtful they would jeopardize their dealership to make a quick buck. Even then, there isn't enough profit for a small shop knowing the OEM's will prosecute to the fullest extent of the law if caught. Although if not a dealer, fair to ask how they got it.

I have the same serial number with a TS2 driver I bought from eBay. At first I thought it was a counterfeit but today I visited an authorized Titleist retailer to compare. The clubs looked identical and also weighted the same (194 grams). This confirms the authenticity of my SF2018 TS2.

Apparently the SF2018 serie is an ex-demo production used by Titleist. However I cannot confirm this with info on the internet. Perhaps Titleist can confirm this?

I believe that is the serial number for fitting heads, SF stands for Sure Fit and the year it was released.

That 2018 might be the year it was manufactured........my suggestion would be to contact customer service.........they should be able to give you an answer........ www.titleist.com/.../ask-a-question

As a fellow Lefty, our clubs don't get counterfeited lol. Wouldn't be profitable as lefty clubs are a small niche market. You're fine