Personally Lee, I'd leave it as is. You could maybe change the colour of the ribbed back padding, to a dark green, semi-matt, to give the appearnce of leather, but again, it looks fine as it is.
It's only fairly recently that I noticed the red/brown seat colours on Spits, as the real ones I'd worked with all had painted seats, and had been done during restoration. In one case, the owner thought the original colour looked like sh*t, and painted it dull silver! Since then, having studied loads of period pics, I was surprised how many seats were that reddish colour, and how many had back padding whilst others didn't, and so on. The three 1/32nd scale Spits I have that have seats (the fourth is a 'hulk') all have different colours of seat!
As Wayne noted, once the rest of the cockpit is built up around the seat, it should fit in well, and probably be a nice contrast.