I think you want M20 TORX headbolts for your M30 325- Any US internet site will have them for $20 bucks. I'd stick with REINZ bolts.

Even in the UK-you must check the headbolts- the old style are weak and the HEX heads tend to snap off. Just open your oil cap and take a peak- if they are hex head they shoud be relaced with TORX bolts. And always remember this is an INTERFERENCE engine-if the timing belt breaks the engine is toast...