Hello both and ‘Bullwinkle’, welcome to the Forum. Great name!
I’ll bow to JT69’s knowledge, but it sure looks like a speedo cable. Seems like on yours the housing has had a knock so this might be more than ‘just’ a cable swap.
I’ll deal with that first.
If you have to change the cable, I think it’s fairly involved. I’ve not done a cable swap but it runs along the RH chassis rail under the driver’s seat. Places where the ‘sun don’t shine’ then loops up somewhere around the radiator to the instrument cluster. The cable is contained on the Electronics Parts Catalogue with the meters (instruments). On mine, it’s:
https://toyota.epc-data.com/regius_ace/lh119v/114894/electric/8301/
Then scroll down (a lot) to Scheme 17! This shows the right-angle version of coupler. Is this yours?
I have the curved variant. This link is for my LH119 van. Modify this for your ‘LH107-xxxxx’ based on your build plate (under LH front seat).
If the cable is fine, which it might well be and I started writing the bit above before I looked properly at the pictures and links it might ‘just’ be where this goes into the transmission and this is where you do need to decode your build plate as this will list your transmission code, which you can decipher on the Hiacesoutheast web site. There are loads of useful resources there, too. These include decent repair manuals and the best electrical manual I’ve seen.
On mine a manual the speedometer driver gear is here:
https://toyota.epc-data.com/regius_ace/lh119v/114894/electric/8301/
You need your transmission code and head into the EPC with the correct option to work out what’s what. As there are a seemingly a couple of threads on the casing part you might be able to metal repair the bits. This might depend on what’s left inside the screw cap. Can the lost bit be reattached or not? Another repair option might be to cut a deeper thread on the casting so it screws onto a new bit though you might need to modify the innards of the coupler. If this is half decent and might hold then wrap the whole lot in self-amalgamating tape or some sort of potting compound for long term support and waterproofing.
I’m unfamiliar with the auto boxes but into the mix I think you need to factor what the lines that come into the casing do and whether you can open this up (good clean first) and remove it. Repair will be easier off the vehicle and this is the route if it’s a replace…
Good luck and
HTH