The breaker you've linked appears to be just fine for the job. Glass fuses tend to be good in places where they are a last line of defense, or otherwise unlikely to blow, but they can get expensive pretty quick if used on the output of transformers as they are likely to blow any time anything derails. For a line only running the switch machines you might be ok with a fuse, but for a buck fifty, I'd go with the breaker.
On the TVS, the folks here on the forum seem to prefer the 1.5KE36CA. These cost 58 cents each from Digikey. http://www.digikey.com/product...%2F54GICT-ND/2407435
Digikey also has a large selection of suitable breakers starting at about $1.36 : http://www.digikey.com/product...-3BA/Q498-ND/1963953 for 5 amp, or http://www.digikey.com/product-detail/en/qualtek/QLB-073-00DNN-3BA/Q500-ND/1963955 for the 7 amp. I would recommend the 5 amp ones for your application. I would pick up some extras as well. It seems a bit redundant, but I would place a breaker on both the common, and on each hot from the KW, as it is possible to have a short between the A and B posts. These are probably not super great breakers, but will be good enough to protect your layout and transformers.
JGL
