That's all you'll need. Lee Tuble Lube bullet molds are designed to be used without sizing, or so I've heard over, and over. Lee has a double cavity mold for a 158 gr. SWC Tumble Lube bullet that will prolly work well in any .38/.357.
http://leeprecision.com/xcart/Bullet...Double-Cavity/ Xlox is available from White Lable Lube
http://www.lsstuff.com/lube/. Cast up a bunch of bullets from wheel weights or scrap lead, tumble them with a little xlox thined with mineral spirits, let dry and load 'em up ( I roll crimp them in the second or third groove down from the nose)...
P.S. A good source of cast boolit info is Lyman's Cast Bullet Handbook