Bulbophyllum aff. longisepalum
Blooming size division in a 2.5" pot available for sale at $45.
Only 1 plant available.
The plant is grown from a cutting of the exact parent plant in the flower images, currently with 3 growths. 
This Bulbophyllum  species has flowers that resemble longisepalum in terms of the shape, however the flowers are more greenish in colour. The flowers are around 10 cm in length.