White spray paint for the hardware?

I'd love if that's a viable option but would think that would create issues with moving parts scraping/peeling the paint coating, i.e. rotating crank arms and especially latches that pop open and closed? To be clear they certainly seem to be plastic, at least in part (as opposed to metal), but I guess Rustoleum might stick. If someone has done this with good results I'd love to know!

See if you can find a piece of identical "stone" hardware on ebay, then try spray painting it as a test.

I just donated a bunch of white grills from our Anderson windows (1987 house) to the local home building products goodwill type store (Chicagoland area). I asked them repeatedly if they even wanted them. They said they had a bunch already, but took them. I question whether ours would have worked with your windows anyway. I suggest you explore a bit to see if there is a similar type place around your area and/or look on Facebook marketplace.

Helpful ideas all, thank you. An update: The crank handle mechanism is still available in white as only the cover plate it attaches to changed in design over the years. I ordered 20 of those babies from Andersen and have also procured Rustoleum spray paint made for plastic (to do the screw cover plates below the handles, which are plastic) and traditional Rustoleum spray paint (to do the latches and screen frames, which are metal).

My husband thinks it's "fine as it is," but it's my hard-earned money and time so he can just be a sourpuss until he sees the improvement as with other things he was initially skeptical about! Ha. Honestly even if this treatment looks imperfect or like an apparent DIY up close, from a distance it will blend into our white windows and in my view that's a big visual improvement so long as nothing becomes less functional, i.e. an interior casement screen sticking. The painted casements themselves sometimes stick and have therefore peeled where they join when closed, even though professionals did that job, which is a bummer -- BUT IT STILL LOOKS BETTER THAN THE 1976 BROWN with our bright and airy home, and the windows still do their job!

As for grills I'll certainly check Marketplace thanks to that tip. Love any chance to both re-use for the environment and save money for the bank account.