Aha, Bustin. I thought mine was standard - until I lost the tensioner pulley!! It actually has had an upgrade pulley kit (175mm dia drvive pulley). I didn't find this out until after I bought a standard tensioner pulley from Toyota ($235!!!) that doesn't fit. And, of course, they won't refund, as it had to get sent up from Sydney.
The closest I can find in the bearing books at work is an SKF with a 62mm OD & 1 35mm ID, which gives room to make a mounting piece that can be 'shrink-fitted' (see yor nearest machine shop) to allow retention of the standard mounting bracket. Unfortunately, as it is only rated to 16000 rpm, it will also eventually die. If someone has the contact details for the guy who used to make the kuits, maybe we can find out from him what bearing he used to use.