Thats a sweet ride, i have a 1982 raleigh competition (much different to yours, light pearl blue in colour and the early 80's raleighs were still doing campag bits. mines a 531, is yours the 501?).
I also have a 1987 raleigh centenary with the same 105 groupset as yours.
Have you tried the frame number decoder (i found it thru google but it only covers up to early 80's bikes, and it can get vague trying to decode late 80's raleigh 501 bikes).
88 Raleigh Kelloggs Pro Tour (Reynolds 501) - owned from new
90 Raleigh Eclipse (Reynolds 501)
82 Raleigh Competition (Reynolds 531) SOLD
87 Raleigh Centenary (Ltd Edition no. 72 of 100, with gold plated Reynolds 531C frame)
88 Raleigh Esprit (owned from new)
90's Raleigh Ascender MTB (owned from new)