'Triathlon' brand bike

[frailer5]

Helped a work colleague buy a retro bike last year from fleabay. She got it at what I thought was a good price. In pretty good shape. Needed a service, but Tange double-butted, and she likes it. In retrospect, curious about the brand, which is marked 'Triathlon' on the down-tube. I'd put it at early 80s, at a guess. Possibly re-badged and aimed at the tri market.
Anyone seen this brand?