Quoted:
KSC, KWA or HFC Glock 18c with extended mags.
The KSC version is about $200 but all metal.
The KWA is the plastic version of the same gun for the same price.
The HFC version is a copy of the KSC and is all plastic but only $122
Lots of accessories and if desired aftermarket upgrades. Parts/upgrades swap between them.
I think you're a bit mixed up. The KWA is metal, without trademarks. The KSC is plastic, with trademarks, but is also available in metal, also with trademarks. (I'm pretty sure that this is the case. I've been out of airsoft for a little while.)
I would avoid the G18c series as a first gun, due to reliability issues. (This is based off of my experiences, and the experiences of others.)
I'd go for a
KWA M19, which is a G19 replica. They can be hard to find, due to Glock cracking down on trade dress issues, though. As of right now, I can't find any in stock.
Oh, and here's a link to their Pro Shop, where they offer replacement parts:
http://store.kwausa.com/
You might be able to order a complete slide and a complete frame from them, and put them together.
-Ed