Man, racekart parts are exspencive in OZ... I checked around and this engine mount seemed to be the best deal I could find:
http://www.ebay.com.au/itm/GO-KART-...Go_Kart_Parts_Accessories&hash=item4841f89c6f
Its got free shipping and they'll drill the 4 holes to match your engine at no charge.
The only thing I'm not sure of, is if it will fit 30mm. and 32mm. frame rail diameters. So before ordering, I'd suggest you measure the diameter of your frame rails and contact the seller to ask.
Also measure the distance between your 2 frame rails, and ask the seller if this mount fits your karts frame rail spacing.
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You've got a few choices for your clutch, Do you want a high quality clutch or a lower cost one?
Does the output shaft of your engine measure 19mm. in diameter, and have a keyway (slot) machined down its length, and a threaded hole at the end, and look like the left end of this pic?
Does your axle already have a hub to mount a sprocket?
It would look like this pic below, and the 6-bolt circle pattern would measure 5.25" or around 229mm.