You may not find a prefilled carto with the flavor your want. You can also try the D1 and Greencig 300/400 cartos at leCig, the cartos at Bloogplanet, the cartos at Vapesafe. Nhaler might have some KR808D-1 prefills. A few here, probably Chinese PG
Vapor Leaf Kings KR808D-1 Cartomizers
Note - I cannot guarantee any of those cartos work - occasionally there are KR8 cartos missing the notches or the cut in the center post. I bought some of the D1's so I should know about them soon.
If you want not sweet also try some camel-alikes or desert ship type flavors (Turkish blends)
My favorite analog flavors are liquids - you would have to use them in a blank carto. You can test juices by using a DSE901 atomizer and cart on a KR808D-1, or the atty with a drip tip if you have manual batteries)
Backwoods Brew Casablanca (a lighter complex Turkish blend w/ cocoa and I add more cocoa these days)
FreedomSmokeUSA Desert Ship (a strong Turkish blend - nutty, pungent, reminds me of a freshly opened pack)
And don't forget to let your nose have some of the vapor. But Marlboros and most cigs in real form have honey or sugar, cocoa, licorice in them. You'll find those in a lot of tobacco juices too. I recommend you get some FreedomSmokeUSA Cocoa premixed juice in a high-PG and your nicotine level. When a tobacco juice is too sweet for your taste just smack it down with that cocoa. I've bought the cocoa a couple of times and it is almost bitter. It will also beef up a wimpy tobacco.