Looks like the part number that you need it 54501-EJ72A. I had to replace one on the passenger's side (blown ball joint), and I went with one from here for ~$300 before tax/shipping.
https://www.infinitipartsonline.com/oem ... Ni1nYXM%3D
Overall, the job was not bad with just jack stands and hand tools, but did take a bit of time.
One question would be why is your mechanic saying you need a new LCA, and is he sure that is the issue...Would be a shame to go through all that, only to find it was a sway bar bushing/end link.