Anglo Bike, who were based in Beenham near Reading was solely owned by Pete Frost.
They were a (Meridan) Triumph dealer. They did loads of tuning working on the T140, T150 & T160 models. They offered half race tunes (cams) & full race tunes (cams/pistons/head work etc) on the road bikes under the name 'Thruxton'
I bought a Half Race US Spec T140 off Pete back in 81. It charged like a Rhino with a hard on yet was very smooth for a Triumph twin.
The models you are may be thinking of were known as Tri-Stars. They were built around a Rob North frame with letter box fairing, Astralite wheels, aluminium tank, tail unit & Brembo or Lockhead brakes. You could either buy a rolling chassis (£2k ish) and supply your own motor or Anglo Bike could supply and build a bike for you to your specification.
Like Dresda built Tritons. No two were the same. I have a price list somewhere so I will see if I can dig it out for you
As far as I'm aware Pete Frost is still around and living the quiet life down in Devon. Last I heard his son Jay was running the business although he now specializes in bring in 60s & 70's motocross stuff from the USA