I had the distinct surprise of seeing GE B23-7 units in Regina last week. On June 11 I pursued CN 1412 to the CN yard in Regina. Once I crested the berm at the south end of the yard, I saw these two units.
The Savage Alberta Railway was a shortline created in June 1999 as Alberta RailNet, owned by North American RailNet. In 2005, CANAC purchased the railway, and on December 1 2006 CN bought it back.
I don't think I've ever seen a GE B unit before. It was a nice surprise to see two of them.
More mundanely, CN GP9 7261 was also there behind them. 7261 is a "mother" to "calf" or "slug" units. Note the extra hardware above the pilot to control "calf" units.