Sorry, but I'm not familiar with any sources of coated HP bullets.
As for the other stuff above, as many no doubt already know...
Most plated bullets are not cast bullets. Most plated bullets have cores that are swaged from pure lead. Most cast bullets are made from lead alloy and are harder than pure lead.
Non-hollow point cast bullets are typically hard enough to stay together and do not expand (or disentegrate). In fact the most reliable and most used bullets for big/dangerous game are probably cast lead alloy bullets (non-hollow point). To ensure reliable expansion of cast lead hollowpoint bullets, some people cast the hollowpoint portion with pure lead, and the area below the hollow point with a harder lead alloy.
Coated bullets may have their origins in reducing airborne lead. But many bullet casters and shooters are using coated cast lead bullets because they are cleaner than lubed lead bullets and often leave little or no lead fouling in the bore.
Lastly, many bullet casters cast hollow point bullets for hunting. The cast HP bullets reportedly work well on thinner skinned game like deer.