Not much out there, is there........I found this, but maybe you did too......who has a Worthpoint Account???? https://www.worthpoint.com/worthopedia/vintage-silverite-spoons-forks-four-168361750
I checked both Rainwater and Davis & Deibel just in case, but since this is one of the "no silver but looks like silver" alloys, neither book has any mention of either Silverite or W P & Co. I would expect the worthpoint description of "likely early 20th century" to be as close as you'll come.
I finally found a site that says they changed from Wm. Page & Co. to Wm. Page LTD in 1936 so it's prior to that, but probably not much more so. I think there is a set of 6 of these so 5 are floating around somewhere. Ran across this one in another box of 'junque' from the attic. Demitasse spoons I think.
I found this possibly useful document called "Trademarks on Base-Metal Tableware" on the website of the Society for Historical Archaeology: https://sha.org/assets/documents/Trademarks on Base-Metal Tableware.pdf It does mention Silverite on pg. 183 but shows a somewhat different mark than is on yours, @Bev aka thelmasstuff
Fig, I've been using that one for several years. You can find some of the most arcane old marks there! I love the fact that you can look up makers by "type" of symbol, too - like BELL, ANIMAL (type...), HANDS, etc, etc, etc. (Not for sterling, of course...)
It does look really very useful! I don't look up many of these types of things but I know that others here do.
