I don't see that Sam Adams is making the Cream stout anymore. They show it on their website as a Brewmaster Collection. I was going to see where you lived and then point you towards some distributors, but they're not making it anymore, that I can tell.

Left Hand makes a Milk Stout and if you're ever over in Neosho, visit my place, Indian Springs Brewing. I'm keeping a Milk Stout on tap these days.