Did Handyman buy off the McGraw-Edison design of something?

Yes,they must have...I know these were Sylvania branded years ago here in Canada.

McGraw Edison was the original manufacturer of these fixtures. Line Material Industries bought McGraw Edison in the 1970's and the ballasts used in these early models were 175 mercury vapor lag 120 volts NPF and "LM" part numbers on them. I have two McGraw fixtures dated 1978 and both the ballasts are Line Material OEM parts bobbin wound with 3/16 in QC' terminals. Cooper Industries acquired McGraw Edison in the 1980's and kept building this design under the regent name but with aftermarket ballasts, mostly Advance transformer

Yeah and the 80s angled-lamp Regent 175w mercury vapor yard lights apparently came with /DX Westinghouse Lifeguard lamps, or so I'm told. There's one at my godparents' house in California with the (supposedly original) Lifeguard lamp and it isn't in use that much. I have turned it on and the lamp is still pretty bright! (Although the ballast has some definate hum and there's a wasp's nest inside that's been there for years)