Hm, Heliophagi are, but then again you need to have blood 5 or 6 and 88 slaves to get them.
What magic are you strong in as far as the summons go? As
trebuchet said, many summonable mages have random picks. Usually it tells you in description that they are "versed in many magic paths" or something like that.
A good bet would also be some indie mages with random picks, such as sages or jade amazons. Do you have any of those? Anythign that has ? for magic pick (and is not Arco mystic) has a chance to get blood, you just have to recruit enough of them to get one.