Dave (Corbin) will hate me, but he has a brother (and they do not agree alot, surprise!) and his brother makes bullet making equipment too. Dick Corbin, Richard Corbin Engineering Company, rceco.com ... Richard has just introduced dies to make quality bullets in heavy reloading presses and a much reduced cost. It would be to your advantage to make his acquaintance. You might want to start here. No idea about demand in your area/country... the muscles are the limiting factor in heavy hand work... if you should go commercial... for yourself, plan well... save a bunch...
Lead cores can be cast or hit the boat shops. Many boating enterprises use lead wire to weight things down. Otherwise, many, many sources of lead can supply it in that form. Many diameters. Both brothers seem to agree, heavy cores for handgun and large rifle bullets are economical to cast. For smaller, lighter bullets... cut the wire.
Basically, it is all cost. I assume you have stumbled into the fact that you can make jackets from fired cases. The ones from .22 rimfire have to be held down as to velocity normal in .22's and .24's, but in competition, the loads are not "barn burners" anyway. The .22 rimfire Magnum case can be used on .26 and .28... You may need to trim to length... Or, yes, budget permitting, get the hydraulic system (Richard has several too) and dies to make your own jackets. It is expensive. Dave (corbins.com) has a used press in the "used" ads last I looked. Dave is a bit more ready to answer questions. Long journey, but a journey begins with a single step... luck and (as Hollywood put if for us) "happy trails..."