Below is an overview of the 76 models I have collected until today.

Back row (from left to right)

1. Charcoal (Old Case)
2. Persian Gray (Old Case)
3. Persian Gray (Flat)
4. Persian Gray
5. Taj Mahal (Old Case)
6. Taj Mahal (Flat)
7. Taj Mahal (Touch Tone)
8. Taj Mahal
9. PTT White
10. Candle Glow (Old Case)
11. Candle Glow (Flat)
12. Candle Glow (Touch Tone)
13. Candle Glow (→ LME manual)

Fourth row (from left to right)

1. Harvest Gold
2. Royal Dubonnet (Old Case)
3. Sahara (Old Case)
4. Sahara (Flat)
5. Sahara
6. Sandalwood (Old Case)
7. Sandalwood (Flat)
8. Sandalwood (Touch Tone)
9. Sandalwood
10. Brown (Touch Tone, → CEAC painted)
11. Brown (North Electric)
12. Brown (→ CEAC painted)
13. PTT Brown

Mid row (from left to right)

1. Aztec Gold Plate (Flat)
2. Aztec Gold Plate
3. Gold Plate (Flat)
4. Gold Plate
5. Chrome Plate (→ my 50th, silver is gold 😉 )
6. Orange BPO
7. Princess Pink (Old Case)
8. Princess Pink (Flat)
9. Petal Pink (Flat)
10. Petal Pink (Touch Tone)
11. Petal Pink
12. Riviera (Old Case)
13. Riviera (Flat)

Second row (from left to right)

1. Mandarin Red (Old Case)
2. Mandarin Red (Flat)
3. Mandarin Red (Touch Tone)
4. Mandarin Red (→ Oslo, Norway dial)
5. PTT Red
6. Dusty Rose (Old Case)
7. Dusty Rose (Flat) 
8. Golden Glow (Old Case)
9. Golden Glow (Flat)
10. Golden Glow
11. Chartreuse (Flat)
12. Accent Green (Old Case)
13. Accent Green (Flat)

Front row (from left to right)

1. Wedgwood (Old Case)
2. Wedgwood (Touch Tone, NEW)
3. Wedgwood (→ Arabic dial)
4. Aqua Mist (Old Case)
5. Aqua Mist (Flat, → NE manual)
6. Aqua Mist (Touch Tone)
7. Aqua Mist
8. Nordic Blue (Old Case)
9. Nordic Blue (Flat)
10. Crystal Mint (Old Case)
11. Crystal Mint (Flat)
12. Crystal Mint (Touch Tone)
13. Crystal Mint

1. 700 White (→ 11 button version)
2. 700 Brown
3. 700 Orange
4. 700 Green
5. 700 Blue

1. Nichco Metallic Orange
2. Nichco Metallic Green
3. Nichco Metallic Blue (Flat, NEW)

Models with so called PBX buttons also exist. I have seen buttons on 2 different spots on the phone, on the side and on  the back.

1. Persian Gray (→ PBX side button)
2. Golden Glow (→ PBX back button)

1. Green Leather (→ Crystal Mint shell) NEW