Would the yarns you suggest get the gauge on size 9s, or be too stiff? Those are really thick for that size needle. The original yarn is an aran weight, not a bulky one and I think the pound o love just might work great.
Hmmmm. . .well, first of all, I mixed up Caron's One Pound with Lionbrand's Pound of Love. The LB is much nicer than Caron's. My bad. I was concerned that the quality of yarn wouldn't be a match for all the work a cabled coat would take, in addition to the gauge issue. But still-- when I looked up "4" yarns, they were suggesting anywhere from 17 - 20 sts per 4 inches. But when I looked at "5" yarns, some of them were 15 sts per inch, closer to the original Unger Cozy, which was 16 sts per inch. I didn't find anything not-too-expensive which was exactly the recommended 16.
I would definitely take your (suzeeq) suggestion of trying the P of L and seeing if you (lovemyknitting) like it, but if not, try those others. My one other suggestion would be to make a pretty big swatch, and also to try a fairly good sized swatch with the actual cable patterns. You want to see how the fabric drapes.