Turbine Technologies builds a miniature turbine with 32/40 lbf thrust with single-shaft and  reverse-chamber (TTL).

“Cutaway drawing of the SR-30”

Turbine Technologies Ltd. is located in Wisconsin, and the first engine was produced in 1990.

“SR-30”

The compressor is a single-sided centrifugal one, and the turbine is a single-stage turbine. See also Kutrieb Research.