If you google on bearings and bushings, we use a plain bearing also called a bushing, you will find a doctoral thesis in info on bushes and materials used, performance, lubrication requirements, and everything else you never thought of. Our bushes are an off the shelf metric size. On some the inner race is smooth, on others it is grooved in various ways. Make sure you get scintered bronze, it is oil impregnated to self lubricating UP TO A POINT. Shooting some grease in the fittings flushes out the shrapnel of normal wear and most importantly the gravel of breakin. Keep clean and it lasts, well, forever. Pop them in the freezer for a day or two for installation. Warm the swingarm up somehow, like in the oven?
DO NOT, pound them in with a mallet or they will mushroom. Should be a slip fit, use some threaded rod and washers to make a press, Use the old rod to line them up. Use a new shaft, the inner bearing part, unless you fell like doing this again soon.
As others have said, Mike at 650central knows his way around these bikes and I would defer to him without shame any day of the week.
Cheers