IPO State Corps

I was wondering if I were to IPO some of my state corporations, how much % of my corp would I need to give away in order to not have to pay for supplies but still get as much share dividends as possible.

I think you are looking at this the wrong way. Every corp pays for supplies. No owner sees profits until the corp meets its expenses, including more the one owner, as in the case of a public corp. You can expect to profit from corps that produce products that are in consistent unmet demand, that are fully upgraded, are located in a country with a good welfare index, purchase the right quality of supplies, reasonable salaries, and have a smart buy/sell strat, regardless of the market price of supplies.