Welcome to the board and back to diving.
If you have what I think you have, a belt with 2 zippered or velcroed pockets, then you can use either regular solid weights or lead shot weights. The lead shot weights are bags of mesh that contain lead pellets. You can make your own weights by making or buying the bags (there is a board member that sells the bags, don't remember their name but with a word search on shot bags I know you can find them)and filling them with # 6 or larger shotgun shot(shot sizes are backwards, 2 is bigger than 4, 4 is bigger than 6, ect). You can find it in many gun stores or buy on line. It comes in 25# bags so shipping can be expensive. If you don't need much, buying them from a LSD is easier. Seems like the average cost was around $2 per lb. I use both but in that type of belt, the soft (shot) weights are more comfortable to me, they will mold somewhat to your sides.