.38 Special and .357 Magnums are pretty forgiving cartridges to reload. They use a large variety of powders and bullets, and you can find a load for everything from hunting itty-bitty spring bunnies to stopping a runaway truck. I started my reloading in '69 using a Lee Loader to reload .38 Specials, and loaded enough to keep me shooting for several months before I could afford a press/dies.
You won't go wrong with an RCBS press, but you prolly won't need all the equipment in the supreme kit. Personally, I prefer to research each tool I need before I purchase and get the one suited for my reloading needs (that's why I have tools/equipment from Lee, Hornady, Lyman, Pacific, RCBS, C-H, and Redding). For straight walled handgun ammo about all you'll need to start is a press, dies, scale, and a reloading manual. Don't worry about trimming, primer pocket cleaning, OAL (just seat to the crimp groove), or tumbling (I reloaded 12 years successfully just wiping each case with a paint thinner dampened rag, and no worn out dies and I could spot any case defects)...