You might want to buy or make a sandbag.
I think you would like using it.
You could handle a 100lb easy for a start.
I'm going to lift it one or two days a week for strength, power and endurance like in the video.
I have it out in my garage.
When I was younger on my job they had a 200lbs dummy for training. I lifted it and put it on my shoulder. Now, I couldn't do it and wouldn't attempt it.