For Heaven's sake, watch Ebay and buy a Lyman #450 (not #45) for about $50. I've seen them at the same price at gunshows as well. The greatly-improved convenience and utility of the lube sizer is well worth the extra set-up cost. From the standpoint of 40 years of casting experience, I consider a lube-sizer ESSENTIAL for new casters. A single flat-faced nose punch will suffice for most bullet types until you want to get a bit more elegant. Additional styles only cost about six bucks each!
Any local gunshop that charges $30.00 for a Lyman sizing die is doing at least a 100% markup and ripping you off, because they only cost about $17.00 from Midway etc. At that rate, I'd say to hell with the local guy. He's not doing you any favors at all.
It's all well and good to want to start "on the cheap", and I've done it, but believe me, there's no comparison between a proper lube-sizer and the rudimentary push-through sizers. They are a false economy, in my book. I do a few bullets via the push-through method from time to time for special purposes, but at least 98% of my bullets are processed through one of my Lyman 450s.
This is the wrong process to economize excessively. Buy a used machine and be happy... and FAR ahead of the game!
BTW, although Lyman and RCBS dies interchange, I find the Lymans are superior for several reasons, including smoother inside finish and a greater variety of lubricant holes in the dies, which allows greater flexibility in selecting which bullet grooves will be lubed.