That is a KISSME connector. As far as I know it is out of production. These systems look good but, have problems with wear and sometimes just falling apart.

The best system I have seen is delrin endcaps with SS pins, like the Marstrom. The H20 is similiar but more complicated because the tiller arms move.

As for bushings a good Ace Hardware should have a selection and Hobie has a couple bushings that might work. If your holes are only 10/1000 oversized you may have problems finding a bushing that thin.