Although commonly referred to as Authenticast, these models were produced by Comet Metal Products. Comet Metal Products mainly known for their vast line of scale military vehicle replicas but did produce some other scale cast vehicles as well as metal soldiers. These miniatures are spincast (centrifugal casting) scale models produced during the 1930s through the 1960s. There is an interesting article about the company history at 87thScale.info. All models I have seen have been full metal construction including the wheels.
Twin/Fageol Transit Bus
Similar to the Twin Coach Model 30 this is the only bus type produced by Comet. These models are near 1:87 HO scale, and have no manufacturer marks.
Notes: I would speculate that this was one of the earlier production runs. I base this on the extra frame reinforcement, and note that the front axle is even crooked.
Notes: Most commonly found in this casting and paint configuration.
Notes: This model appears to be original. However, it may be a later production run made by another manufacturer after the Comet molds were sold off.
O Gauge Bus Stop Scene
Red, silver and green variation.