ANyone have or know where one could get a tranqualizer gun?

Try Nasco Farm and Ranch. https://www.enasco.com/c/farmandranch/Cap-Chur%20Equipment/

Wild cow problem?

LOL I wish, try raising huskys sometime! The damn things are escape artists.

That Cap-Chur will calm them down...

I have one and have used it quite a bit on wild cows. 2-3 CCs of Xylazine and they are much easier to handle.