tensioner and idler pulley bolts

[-JELLY-]

does any1 kno wot size are the bolts used for the idler pulleys and tensioner on a late type let? i hav rebuilt an engine and cant find origanals to match anywhere! the parts guy my local vauxhall dealer is a ryte cock an is no help wotsoever :eek:

[blue_peg_16v]

you get new ones with a belt and tensioner kit if the engine has just been rebuilt id invest in a full kit