By looking at this, can anyone tell me, how many gems I need to use more in order to complete this quest.
you still probably have to waste around 4,000 gems in your case. You should wait the blacksmith event where the profit is better. 2:1 instead of the default 10:3.
If the angle is correct (and 360° stands for 10K):
Should be around 1,2K Perls to buy left.
Thanks! This means, I should not waste my current amount of gems in order to get it. As, I dont have 4000 now