Crozza... bushes need to be very accurate or the very purpose for having them is wasted. "I think 8mm" isn't accurate enough. If you know what you're buying you could try VicMTB on (03)9817 2917 because they have a fair range of bushes in stock (last I heard)
OR if you're not sure what to ask for you take your shock, the bolt that goes through it AND the frame where it connects that bolt and shock to a decent engineering shop and they will make what you want.
Don't get fooled into asking for or thinking you're going to get sintered bronze bushes because A/ they are not only unnecessary for this type of use but B/ sintered bronze is pressure-cast powder metalurgy and NOT machined or machinable.
I mention this here on this thread about bushes for everyone's general knowledge and info because some places will tell you that you have to have sintered and charge you heaps when in fact they aren't supplying that at all.
Crozza... ask your friendly, honest engineer to turn up the bushes per the measurements HE will take for you and do it out of brass or vesconite... either is fine for the type of wear a shock mount is subjected to... which is virtually no rotation (meaning the self-lubricating properties of sintered bronze just isn't needed) and all compression.
Sorry for the waffle... hope it helps.