Sadly, DDNI, there are too many hints to refute this as an Amiga..
The distance between the Function Keys and the top of the keyboard device is way too short. For an A500 this is nearly half of the distance from the bottom to the top, as you look down onto it. The A1200 is a bit shorter in this respect, but if this was late 80s, then the A1200 would still be a few years away.
Also, the colour of the F keys, along with the outer keys (Return, Shift, Tab, 'A', etc) are much darker in relation to the Alpha keys on my Amigas, so, unless there were some differently-coloured keys produced, I think it looks to be a normal, boring PC keyboard.
However - it's a great spot. Well done for picking it up and posting it, as it would've been great to get a positive result. Always nice to see a miggy kicking about in TV programmes of old