I found some little DC-DC stepdown regulator boards on AliExpress a few months ago. They use an LM2596 switching regulator and provide up to 3 Amps depending on the model. The ones I got were about USD $20 for 5 pieces delivered. Another ACL member found a similar item on eBay. There are a heap of variants, but if you search for LM2596, you should find them easily enough. Others have bought larger (higher current) versions that appear to be potted (epoxied) into a metal case / heatsink. These boards could be used in display elements, dropping some common supply voltage (24V DC for example) down to whatever the item needs. I encourage other members to post about the ones they've found and used in their displays.