Black composite. Thinking about selling. What kind value do they have?

Not much, 'cause Winchester/Olin hasn't made much of a commitment to support any of the three WSSM cartridges.

Winchester must just have shipped a new batch of ammo, I was in a shop in PA that had plenty of WSSM ammo

Yes, I know that Winchester/Olin has made a limited/seasonal run of WSSM ammo, but there is no way to know how often they will make these runs in the future.

Annually?

Bi-annually?

And, even if they do make the ammo/brass, will they spend the $$ for new forming dies or will they let the brass quality go to $hit when the dies get worn, like they did with the 284?

You worry too much
WAY TOO MUCH
It did not stop me from buying a 22-454. One run of brass was made, EVER

For the past few years, many WSSM shooters stopped using those rifles, or they have opted to pay usurious prices for ammo, due to the shortage of ammo and/or component brass. Since the WSSMs are all orphaned, no manufacturer that I know of is cataloging them, and Winchester/Olin is only making "seasonal runs" of ammo, but not on a regular schedule, and, maybe, component brass, I'd opine that buying a WSSM as a "shooter", rather than as a "collector", is an "iffy" move.

That doesn't mean that I don't think that the WSSM aren't good/useful cartridges. Heck, if I did, I wouldn't have two dozen Winchester/USRA 70's chambered for the three WSSM cartridges, but most of them are NIB "collectors", not "shooters".

I don't have to worry about WSSM ammo or component brass, as I have a lot of 25 WSSM ammo and Federal 223 and 243 WSSM component brass on the shelf.