Hi, To be honest they could be any size and type depending whether they are originals or aftermarkets, By originals I mean OE replacements. Later or more modern one may be built using pins with metric threads, that's not really a problem because they are supplied with nuts. Having said that there won't be too many choices because they will be limited by the size of the pin. So just measure the diameter of the thread and the TPI using a gauge, an online thread chart will tell you what it is.
Colin