Minolta U.K. had a great tech guy doing both lenses and binoculars. I forget his name.
After Minolta closed he carried on repairing optics, but I didn't keep in touch after a while.
He probably also had others on the repair team.
I dropped my Minolta SRT 101 from 16ft onto concrete photographing the abominable comet Kohoutek I think. The top was smashed and my insurance had it 'repaired' by their own non repairer. It took a year. I bought a replacement straight away.
When the original came back I forced the insurer to send the terrible repair to Minolta, who did a comprehensive full repair, not a replacement.
Minolta, Canon, Nikon and Vivitar and Leica had world class repairers in the U.K. Vivitar U.K. had I think the best optical bench in the U.K.
At head office Mr Pettigrew had an encyclopedic knowledge of all things Minolta.
Minolta club members got free annual checks and servicing.
Yes, sometimes a replacement is the cheapest option, But Minolta were capable of top quality repairs.
The 58mm f/1.2 Rokkor was fast centrally, but only f/2 at the edges. I had published photos of Aurorae and noctilucent clouds that I took with it. 1 second at f/1.2 for NLC, 4 seconds for Aurorae.
I also got a comet and fireball in the same frame at 14 seconds about at f/1.4 with the 50mm f/1.4.
The SRT 303b had the neat trick of moving 1/3rd frame if wound with the bottom button pressed I think. This gave 111 photos of Saturn or Jupiter on one roll of film. 1 second at f/72 with the 317mm DK, i.e. ~ 23,000mm at f/72. High speed Ektachrome 160 ASA. The photos were impressive, at least the best few on a roll.
In the era your talking about I'm pretty sure Samuelson Film Services had the best optical bench. They had a complete stranglehold on movie rental equipment in the UK which is built and maintained to exacting standards. Now incorporated into Panavision