I got a Bosch ignition switch from AutohausAZ.com for about $50. It does indeed have a push-in to turn-to-start feature.
I bought a pushbutton from NAPA for about $6 in the early 2000s and it's still working just fine. I put a 30 amp Bosch relay on the switch, so it should last forever. Terminal 85 to switched ignition. Terminal 86 hooked up to a good under dash ground. Terminal 87 hooked to 12v hot all the time. 87A goes to the starter wire back to the engine. Easy.