What year is the car? I have an early sales brochure which shows a limited range of colours like John has posted but I also have a later brochure which shows a much more extensive range of colour options for the later cars. I'm sure it shows a few more different greys. I also have a workshop manual with an extra page inserted which shows a larger list of Alpine paint options and their codes. I'm in work at the mo so can't check but will have a look when I'm home.
EDIT:
Just got in from work and had a quick look-
My brochure dated 07/87 lists the colours:
Supergloss Red 075
Supergloss Black 655
Supergloss Metallic Silver Grey 069
Supergloss Pearl White 168
Supergloss Metallic Titian Red 076
Supergloss Metallic Stratos Blue 436
My brochure dated 07/89 lists the colours:
Supergloss Red 075
Supergloss Black 655
White Gardenia 303
Supergloss Metallic Silver Grey 063
Supergloss Metallic Granite Green 609
Supergloss Metallic Champagne Beige 132
Supergloss Metallic Alpine Blue 488
Supergloss Metallic Sports Blue 449
Supergloss Metallic Red Ecollette 776
The manual technical note states:
'You will see that we have added to the range of Alpine paints, the list of Matra Espace colours which can be applied to the GTA V6 or GT V6 Turbo, upon special request.'
and lists for the MODEL YEAR 1989:
ALPINE:
Pearl white 015
Silver grey 069
Black 655
Bright red 075
Gardenia 303
Navy blue 048
Titian red 076
Beige 132
MATRA Espace:
Brown 174
Iceland blue 447
Titanium grey 647
Cornelian red 742
Sardinia brown 144
Blue 436
Carbon grey 662
Meteor red 707
Atlantic green 905
Manchurian blue 437
Emerald 988
Vesuvius red 712
Ambergris 609
MODEL YEAR 1990:
ALPINE:
Bright red 075
Black 655
Titian red 076
Pearl white 015
Silver grey 069
Blue 449
Alpine blue 488
Beige grey 132
ALPINE "LIMITED SERIES"
Scarlet (supergloss pearl) 776
MATRA Espace:
Brown 174
Iceland blue 447
Titanium grey 647
Cornelian red 742
Sardinia brown 144
Blue 436
Carbon grey 662
Meteor red 707
Atlantic green 905
Manchurian blue 437
Emerald 988
Vesuvius red 712
Ambergris 609
Judging by your picture Martin and looking at the later brochure I'd say the colour looks like Supergloss Metallic Granite Green 609. Interesting that in the manual this is listed as a Matra colour and they call it Ambergris 609.
If I get a chance later today I'll try and scan the brochure colour charts and post them up for you to see, as Johnc has done. But now I'm going to bed because I've just done a night shift.