I would recommend a 600cc Mini Sprint. I loved my time racing them. I think about buying another one all the time and I'm 61 years old now. Lol. There are many different classes Winged and Non-wing. Even a senior class. US 24 Speedway in Logansport runs every week. I not sure if Miami County Fairgrounds Speedway (Peru) is still running every week or not. Many of the Central Indiana Dirt Tracks also run them from time to time.

A lot of the sprint car stars of today started in them.

A TQ Midget would be another option. Even Tony Stewart still races one from time to time.