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No, 1/48 is the rare upper limit. Most of the bigger kits will be the Perfect Grade at 1/60 scale.
A few years ago, Bandai did release a 1/12 scale Gundam and Zaku, though. Price, around $3,000.
http://gizmodo.com/192169/human+sized-112-scale-gundam-rx+78+2-giant-toy-robot-not-yet-big-enough-to-pilot
Here’s a 1/12 scale Zaku up for auction on Yahoo Japan
http://page2.auctions.yahoo.co.jp/jp/auction/b115310252