AuotZone. I think Oreillys offers them too and probably Advance/Carquest. Can't tell you if any one is better or worse. There are also Crankshaft Supply in MN and Ohio Crankshaft.
On your pistons, the tallest stockish ones out there are the Sealed Power H814CP's. There are taller pistons out there (for higher CR) but they are all lighter and require some minor crank balance work. That crank work could be simple but takes a few steps and a cooperative shop.
Higher CR works to help lower RPM torque, mainly down in the under-2500 RPM range which helps make it better for grocery-getting type street driving. If you wanted to improve that, then I'd suggest a few options:
those H814CP pistons, and the thinnest head gaskets (Mr Gasket 1121G); look under '95 5.2L Magnum for that piston
mill heads .040" or .050" and use the standard Felpro kit head gaskets and those same pistons; this will push CR up over half a point from the stock leve