TH350 transmission dipstick tube

[Dano71]

I apologize if the answer to this has been posted elsewhere, if it has I couldn't seem to find a current (2016+) source of info.

I have a TH350 (71 Blazer) that leaks profusely from the dipstick tube. The one I have is an o-ring style and the previous owner piled on a mountain of RTV to get it to seal. It is no longer sealing. The bellhousing bracket was also not bolted up and appears to be JB Welded to the tube in an incorrect orientation.

So...

Where can I find a replacement tube? Ideally something original or something with the grommet style seal. Are these still available in the junkyards? I'm surprised not to see one available from LMC truck.

I've seen two different mounting configurations: one on the upper bellhousing bolt and the other on the mid bellhousing bolt (3 o'clock position). Which is correct for the Blazer?

Any info would be very much appreciated...thank you.