Magnetic ballasts for F40T12 luminaires were banned under the same law banning incandescent light bulbs. You can still get F40T12 ballasts but they are only available in electronic flavor.
Maybe you could give the kitchen a new look and replace the fixture. Light fixtures are not that expensive at Lowe's Depot.
I installed some hardwired F40T12 fixtures in my basement back in 2010 (that contained electronic ballasts) and the light they produce is amazing compared to the screw base bulbs that were there before.
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