OBNB doesn't sell books, but you may be able to find a copy at one of these websites:
Fihris makhṭūṭāt baʿḍ al-maktabāt al-khāṣṣah fī al-Yaman by ʿAbd Allāh Muḥammad Ḥibshī. ISBN 1873992122. Published by Al-Furqān Islamic Heritage Foundation in 1994. Publication and catalogue information, links to buy online and reader comments.