Those Mk I interiors really take me back to my first selling job in a Peugeot dealership in Watford in 1988. The 405 had just been launched and there was a lot of interest in it. They really were a superb drive, hope yours still has that unmistakable Peugeot 'feel'. The 205 and 405 had the best steering feel of any car I have ever driven.
It may be the only topaz blue SRi left but there should be a few topaz cars around in other trim levels, it was quite a popular colour. Two early 405 colours which have completely disappeared are Panama beige and Calypso blue, both fairly weird solid colours.
I also remember some of the appalling quality on some early 405s, they were making them too quickly. One beige saloon we had the rear door skins actually flapped about as you shut the door, we also had an automatic with a loose clutch pedal flopping about.
It still has that feel . My first 405 was a black Sri in 1991 and this feels the same. My sister and her ex husband bought a 1987 E plate GE which I think might have been calypso blue it was a solid sort of french blue. It was a 1.6 with no power steering but that was a very eager car.