Since I have no experience with a "kit", I will just relay how I got started.
It was in around (I think 1970 IIRC) and I had not a lot of money as I was a youngster just starting college.
I bought a Lyman pot (call the Lyman Mould Master Electric Furnace) and I don't recall what I paid for it but it seems like it was about $35. I ordered an RCBS mold for around $15. Then a while later I ordered another in 357. Along came the RCBS lubrisizer. I was in business.
I did not know what the hell I was doing, but I was making some beautiful cast bullets. Added a bunch since then.
Present day, my favorite molds are made by Accurate Molds. Aluminum, brass, and the traditional iron molds are all available. I like Accurate because the are CNC cut and can be purchased as is or they can be modified to almost any specification that you want.
I have Lyman, H&G, Ideal, RCBS, and Accurate molds and I don't have a bad on one in the lot. They are all iron molds.
So, lastly, I can and do make cast bullets for every caliber that I own.
By the way, the Lyman Mould Master Electric Furnace is still working and I still use it often. I have a larger pot for melting lead and alloy to make ingots for storage. My large dipper will fill a 4 ingot mold.
Alloy and lube is the secret to successful cast bullets.
I get my lube from Leah & Glenn at LSStuff.
http://www.lsstuff.com/
Here is an excellent read on bullet lubes:
http://castbulletassoc.org/forum/thread/13059-testing-bullet-lubes-at-3000-fps/
Good luck and I know you will enjoy shooting bullets made by you. I do.
Casting bullets is the only way I can afford to shoot my big bores regularly.