OEM may still be avail at Toyota, part number 04453-60021, and here is a link to a whole sale toyota place (and there are many of them), I don't work there, in fact they are in Texas and I am in Idaho also a web site for DYI part numbers, great site for Part numbers and then go to Toyota site, if you get a price you have a 60% chance it may still be available, call them and they can tell you.
OEM parts (most) are unavailable and expensive as hell. I found the entire joint w/ housing from MAF for 99 bucks. I tried a rebuild kit that was junk, then another from sor only to find the housing was messed up. I dropped in the unit from MAF and never looked back. The part was made by Fuji or something come to find out it was a toyota OEM manufacturer. That's my .02 for what its worth. GL
I just tried ordering the whole assembly from MAF about a week ago. I was told that they are out of stock and do not know when/if they will be getting more. I will be rebuilding mine with the SOR kit if I end up not buying a low mileage used unit. CCOT has a better price on the rebuild kit, I think, but I prefer doing business with SOR (just my .02)