http://www.neweramodels.com/item.cgi...=&part_id=2963
http://www.wheelextensions.com/index_files/14mm
http://www.junfac.com/shop/index.php...f071ae71433b16
You could also use these:
http://cgi.ebay.com/Pro-Line-23mm-He...item2eb5ed65b0
or these:
http://cgi.ebay.com/Ofna-30059-17mm-...item45fba835fc
But you'd need a sleeve over the axle to take up the slack- 6mm axle vs ~8mm inside diameter of the extension.
If you were using the teknorc knuckles with the 8mm axle option, they would be a direct fit...
http://www.teknorc.com/product_info....roducts_id=988
I suppose you could just use the optional stub-axles, but then you'd have to find some odd sized outer bearings to suit the stock knuckles.
http://www.teknorc.com/product_info....oducts_id=1083
stock is 6x12x5, you'd need 8x12x5- a quick google does turn up some results so it is a possibility...