You do not have a 143.5mm chainline. Most are from 42-52mm. Read Sheldon, check your measurements and terminology, and try again.

That said, I'd guess you meant to say you have a 43.5mm chainline. This is pretty good. A difference in chainline of 1.5 mm is pretty damn negligible in my book. If you must fine-tune it, see if you can get a 108mm spindle. This will move each crank in 1.5 mm (3mm total length change), thus giving you a perfect chainline. Alternatively, you could get a 1.5 mm spacer for your cog. As long as you still have plenty of thread engagement on both the cog and lockring, this could be the way to go.