olds 307 and 403

Found one made on a jig for a G body, $500. Set up for GM brakes with a 489 case with 2.94" open gears. Just needs axles, from what I can tell they are bolt in 30 spline. Yukon makes a cut to fit set cheap but has the Mopar 4.5" bolt pattern and "green" axle bearings only. I am looking at $750 for a decent posi and axles for my 7.5". Thinking this should be much stronger. Thoughts?