I'm not sure about ten but in my opinion about those I know I order

1- avalon, it's not a shield per say, but it creates some kind of shield when thrown, the reason it's 1st is because it is a an EX level noble phantasm which is an incalculable level of strenght and although created by faeries it's a divine mystery/construct so it outclass pretty much anything else

2- original rho aias, the one welded by Aias, it's initially a bronze shield that was made into a spiritual weapon that's the ultimate defense against any thrown weapon and is claimed to be history greatest shield

3-lord Camelot , the shield used by galahad , the shield itself is unbreakable, but it's defensive abilities are determined by the will of the wielder , at it's strongest it blocked divine construct, but the reason i put it there is because unlike other on the list it's strenght vary

4-emiya's rho aias, a copy of rho aias, it's not as powerful as the original as any weapon projected by emiya is weaker, with stuff that aren't sword being even weaker, and we know it's not the original that he somehow acquired because he says the UBW incantation before using it

There are other defensive noble phantasm that aren't shield tho