How much will it run me to change my 355 into a 383? What parts do I need and will I beable to keep my components now? How easy/hard will it be for me to do it myself?? specs in sig:

 

Search around for stroker crank kits. You'll get prices, and be able to see what parts are included. Typically you'd get a crank, shells, rods, pistons and pins, ring set, bolts, and possibly gaskets. You can keep you entire valve train, but you may find that a stroker is going to like a little more flow (and fuel).