Well I broke down and bought a TRD axle from Shannon. I know I spent more than fixing the bearings, but I've been more than busy with side jobs to help offset some cost, and when I pulled out the lincoln I realized it sucks not having a rear locker and it was such a sweet deal, cheaper than an ARB. Hopefully I will be getting it end of the week. I also have to replace the carrier bearing.Wow, how did that happen?!
Anyway, I've never grenaded mine, but I had them replaced on my old 99. Whatever you do, don't take 'em to a shop that's never done Taco rear wheel bearings. Also, I would strongly advise against the trail-fix method of slamming the axle end on the ground to get the bearing retainer and bearings off. I know others have done it with success, but when we tried it at the shop, the axle ends mushroomed badly, requiring me to file them down for hours to try to get them to fit back into the diff. We ended up torching them off (the bearing retainers), which just caused other problems later on.
Instead, I would just take the axles off and take 'em to the dealer or any other reputable shop with Toyota experience. It cost me about $100-$120 at the dealership to have the old ones pressed out and the new ones pressed in (after the shop I took them to screwed it up and even managed to put the bearing retainers on backwards). It's been so long ago, though, that I don't remember if that price was just labor or if it included the price of new bearings.
As for spares at a junk yard, please tell me if you find some. I've looked around the local yards in vain for years for spare axles and other spare parts, all to no avail.
Hope this helps.