Vacuum line questions

I have a 2015 trd sport.
So I have a old school Hadley air horn setup. The compressor it comes with runs off of vacuum.
So I was wondering if there are and spare vacuum ports that are plugged up. Or if there is a safe vacuum line I can tap into. I'm not sure how much vacuum the pump will use. So I'm hesitant to tap into a line. My other option would be to tap into the air intake somewhere before the throttle body.
I did a test and pulled off the brake booster line and it has enough vacuum to run the pump. I just need somewhere to tap it into.
Thank you guys.

 

Bump

 

Maybe a "tee" into the brake booster line

 

There's a reason vacumn wipers ended back in the late 50s.

Sharing the feed for the brake booster with the horn, two things likely to be used together, just strikes me as risky.

Any chance you can convert the compressor to 12v and still use the horns? Or replace the compressor with a 12v one? While a compromise of sorts, you'd still have the same sound and the look of the trumpets (if you are trying to display those somewhere)

 

i can i actually have a 12v compressor but its mounted in the bedbox. and the air line is to long. this setup works. so if i could taap it that would be nice. what you think about tapping the intake pipe