I did a brief polish of my bell with Mothers Mag aluminum polish and it turned out great for the little time I spent doing it. The thing I learned with this polish is the more time you put into polishing with it, the better the shine. It works really well on the bell steel and I've used it on different metals with great success. You may want to first do a high grit sanding to take off the first layer, and then do the polish.
This vid shows how it works on stainless, but you may be able to achieve this level of polish with some effort. Pretty great bang for buck, IMO.