Its very similar to the 1098-1275 slave but a little shorter. on the back end as part of the casting there is a block with the bleed scru and inlet fitting. The pushrod is threaded.
Look in a paper pictorial catalog, Bendix, Centric or whomever in the clutch slave section.
this is a discription of the oem Datsun/Nissan piece that came on those trans. "form Rivergate might have modifications for the Spridget throw out arm. And BTW there is three different bores availaible.