What is this and where can I find the replacement?

Hi all! (Hopefully i flagged the post correctly!!)

I am needing to replace this part for a 1999 Volkswagon Cabrio. The speed sensor is on top of it and by all google searches- I see its a speed sensor assembly/pinion? I took the part to orielys and they said they dont have the part or anything like it.

So my question is- where can I find a reliable place to replace this part? I am going to use ebay as of now and my follow up question is; would replacing this fix the speedometer? I replaced the actual speed sensor with the 3 prongs and my speedometer remained unmoving/littering. If not, what should I try replacing?

Thank you in advance!

https://imgur.com/a/AeoIZyp (image of the part!!)