Should I spend the 169 to 200 dollars for a new brake booster or buy one at the junk yard for my 69 chevelle?
Thanks

Considering safety and all the work involved changing the booster, I'd definitely go with a new one. No fun if it craps out, even if it doesn't cause an accident, you'll have to replace it again.

If you don't care about the appearance (I guess you don't if you're talking about picking it up at the junk yard), you can find retrofit boosters for about $90-100 at Napa, Auto Zone etc, and for another $30 or so you'll get a new master cylinder to go with it.

Shop around a bit. I got a rebuilt booster (Cardone , I think) and the prices that I got from the local stores was from $75 ( I bought) to $150. Try looking at both Autozone and Checker web sites for easy comparison shopping. Getting one from a yard might work, but it is still an old used part.

There is a guy here in MI that rebuilds them to orginal spec. He sandblasts them, CAD plates them, put all new seals and stuff and check them. Last time he charged us $120. Which I thought was a deal