tyro so I don't know how do-able this would be
Not at all. We used to be partnered with Unixstickers however when they switched how they sell stickers (now in bundles), they dropped the Solus stickers without informing us. Until we have a legal entity behind us that can handle all the profits we get from merch partners, this isn't something we're going to partake in (none of us want to take on the legal or financial burdens), and for obvious reasons we don't consent to anyone creating merch using our branding without coming to clear arrangements with us first (and any merch out there currently is done without our consent or forwarding of any profits / proceeds to us, and shouldn't be linked).
I too would ideally like stickers again, t-shirts, hoodies, a beanie (cap), etc.