Official Pinyin of 《卜》 in 《卜姓》： "Bǒ", "Bo" or "Bǔ"? I've chosen a family for my Chinese name. I derived it from "Булыгин" in Russian. So of course there are no relatives to explain it to me.

This family is rare, and in the English Wikipedia I can see no page for it. Also, all families there are without Pinyin marks, and I have impression that they are not just Pinyin without marks, but romanization, "o" changes to "u" there, and 《卜》 becomes "Bu", like in Russian. In text to speach engines it indeed sounds like "Bu". Google Translate interpretes 《卜姓》 as "Bo xìng", with zero tone, and in another sources I have found that when being a family it should be "Bǒ" in the third one. Baike gives error 500 if I try to click 《卜》 in 《百家姓》 。 Japanese Wikipedia has a dedicated page, and Pinyin is stated to be "Bǔ" there. I'm lost. Where is the truth?
This family name is very rare. I personally don't know anyone around me with this family name. The authoritative dictionary "新华字典" lists Bǔ as the correct pronunciation for the family name. 

The pronunciation "Bo" (neutral tone) is only used in the word 萝卜, which is a plant (radish), and we even have 胡萝卜(carrot).