Used a predecessor of the Mec 600 Jr. for about 25 years - no problems, replaced wad fingers about half a dozen times and a cam-roller twice.
Loaded thousands of shells on it. Eventually went to a MEC9000G and then
on to Ponsness-Warren. Have had the PW for 5 years.
The Mec 600 Jr. should do all you want to load bismuth, but you should be able to buy Kent Impact for about the the same price as your reloads. Last I checked, retail on bismuth shot was +/- $ 175 for 7 lbs + applicable taxes - that's about $ 201.25 here in Onatariariario. That will yield about 112 sells for you ( 1 oz. loads ) or about $ 1.79 per shell or about 89 shells if you load 1-1/4 oz. at $ 2.26 per shell, which does not include the empty hull, powder or wad !