Welcome over to the floaty side Ian. Two answers to your questions. There is no "normal" scale for ships. It really depends on your space constraints, cost, eyesight, etc. 1/350 and 1/700 are probably the two most popular ones, with 1/600 being a close third. I assume you mean USS Tuscan, an Atlanta class CLAA named after the 2nd largerst city in Arizona? There is a kit of the USS Juneau, a sister of the Tuscan, in 1/350 in Resin, but it's over $150 normally. There is a 1/700 DML kit USS Oakland that is apparently a reboxed Matchbox kit of the San Diego. They're all, Tuscan, Oakland, San Diego, etc, are sisters of the Atlanta so any Atlanta class cruiser should work.  Here is one link to the Matchbox kit. 
http://www.modelwarships.com/reviews/ships/cl/cl-53/700-mb/sandiego.html