rdnzl
I can't speak to the 7x35,but I have an 8x30 that looks just about as mint condition as yours. Mine was made in 1950. For a binocular of that age it works a lot better than most would think possible. It is not as bright as something like my Nikon Aculon, but I would not call it dull, nor say it was lacking contrast. I used it a bit the last couple of days and would have no concerns about needing something better if that happened to be the only binocular I could lay hands to. The big difference in my 8x30 and your 7x35 will be field of view. The 8x30 claims 445', but measures something like 460', compared to the listed fov of 393' in the 7x35. I've never used a Zephyr 7x35, so can't comment on comparative brightness between the two.
One word of caution. When I got mine I was assured that it was in perfect condition, and matched the pictures. When it came out of the box it was covered in what looked like a thick nicotine film. I could not physically force hinge movement, nor force function from the focus wheel. I had to raise pure hell with the seller and was able to get them to knock down the price. For the price difference, Nicholas Crista restored mine to brand new condition.
It what you are after is a fine example of an excellent classic porro binocular, still useable in today's world, you have made a good choice. Don't obsess on what the spec sheet says it does not have and I think you will get along just fine with the Zephyr.