Considering items above 500k we have:
We can sell to NPC Yasir:
650 000 gp - Abomination's Eye 
700 000 gp - Abomination's Tail 
950 000 gp - Abomination's Tongue 
630 000 gp - Beast's Nightmare-Cushion 
720 000 gp - Cruelty's Chest 
640 000 gp - Cruelty's Claw 
3 100 000 gp - Figurine of Cruelty 
2 900 000 gp - Figurine of Greed 
2 700 000 gp - Figurine of Hatred 
2 800 000 gp - Figurine of Malice 
5 000 000 gp - Figurine of Megalomania 
3 000 000 gp - Figurine of Spite 
950 000 gp - Greed's Arm 
500 000 gp - Maxxenius Head 
1 900 000 gp - Megalomania's Essence 
1 500 000 gp - Megalomania's Skull 
5 000 000 gp - Morshabaal's Brain 
3 250 000 gp - Morshabaal's Extract 
840 000 gp - Spite's Spirit 
737 000 gp - Vial of Hatred 
We can buy from NPC King Tibianus
500 000 000 gps - Golden Outfit
250 000 000 gps - Golden Outfit Addon 1
250 000 000 gps - Golden Outfit Addon 2


We can buy from Trader NPC's
945 000 gp - Durable Exercise Axe 
945 000 gp - Durable Exercise Bow 
945 000 gp - Durable Exercise Club 
945 000 gp - Durable Exercise Sword 
945 000 gp - Durable Exercise Rod 
945 000 gp - Durable Exercise Wand 
7 560 000 gp - Lasting Exercise Axe 
7 560 000 gp - Lasting Exercise Bow 
7 560 000 gp - Lasting Exercise Club 
7 560 000 gp - Lasting Exercise Sword 
7 560 000 gp - Lasting Exercise Rod 
7 560 000 gp - Lasting Exercise Wand 