Where are you going with this cultipacker? Easy farmland, or trucking through some rough woods. IF the traveling will be rough, you should go with less width and less weight.
Even a land roller filled with sand can be a pretty mean foodplottin tool.
Im tossing around between building a food plot seeder with 2 4 inch spiked rollers behind some disc and having a clover and grain box ontop. Plan B is a single cultipacker or roller with a detachable clover seed box. I have all the parts for the seeder. I have both 12 inch culvert pipe, and a 22" diameter steel tank. I have a old trailer axle I can rig up to make it a flip one. Either one I use will be 36" wide. The steel tank will be left empty, but have a good sized drain plug. Flip the roller, drive it in with water. If it's too much remove some water, or fill it when I get there. I have a 600 acre hunting lease with a 1/2 mile of road frontage. A snowmobile trail goes alongside the road, sometime 100 yards back an right next to the road in one spot. I got the 1/2 mile trail and 3 small 1/10 to 1/8th acre plots I seed. I have a log landing right by the road I can seed up this year too. If the snowmobile trails come out ok this summer without needing retilling, I got a 1/2 acre plot about 1/2 mile back in the woods. I got a decent path to it, but theres a rutted up section with a mud pit on the end. The emptyable feature of a roller might make or break that spot. Worse comes to worse, I have made plots with just the atv tires alone.
I sort of abandoned a portable cultipacker idea. I had about a dozen 8 inch tires. I was going to offset a front and rear set with a flat top frame I can add rocks ontop of it. I got a bunch of cultivator teeth I could put on the top. Flip it over and have a portable seedbed rippere / basic leveler.
As you drive around, just ride the next tire rut on the last, and the cultipacker will handle whats between the tires.