NMP:
Here is 295xxx which is very similar to 265xxx which is about the same year as yours. There are minor differences regarding the info on the end sticker. 2 line address on the top, of course.
Ed
As I understand it, S&W did not throw anything away. If they had Gold boxes available they would be used. As far as S&W was concerned, a box was a box. They did not switch to the blue box on a specific date and I am sure the use of the Gold and Blue boxes overlaped during the mid 1950s. For your gun either the gold box or the blue box with the solid silver line around the edge would be correct. You do not want the blue box with the dotted silver line and the words "Bangor Punta",as these were not used until mid 60s. You might want to letter the gun and see when it was shipped. While the SCSW indicates your gun was manufactured about 1955 it may have shipped much later. Smith17s K 295xxx was manufactured about 1957 and could have been shipped later. If you do letter your gun and find it was shipped in 1955, there is a better chance it was shipped in a Gold Box.
Wow, S2, that is one beautiful group! Thanks for the tips, all. Only one candidate that's close from me right now on flea-bay, a gold box, but with conflicting info as to barrel length and going over $71 right now. I hate that folks don't keep their original boxes!