Okay....I have read all the brake booster threads I could find and here's the deal.  My car was built in July of 1972 and has the small six inch booster.  From looking at the threads on the subject there supposedly was a change over in June of 72 to a larger booster that was carried over to the 73's and on.  I'm thinking my car probably came off the line at the very tail end of the small booster build out.  So anyway I'm thinking I should ignore ordering by year and concentrate on the size which would be from a 1971.  If I order a 72, from what I can tell, I'm going to get the larger booster with a different bolt pattern. 

I would order one for a 1970/71.

 

Chuck

Can you even get the small boosters anymore? I had not seen one anywhere recently.

Charles

I bought one from rockauto.com about 2 months ago, $106 with $27 core charge so it was $92 after paying the shipping back to NY of $13.  The top left nut inside the cabin took me longer to remove than installing the whole thing.  You can lay a short peice of wood across the inspection lid to the front of the wipers making a triangle to hold up the brake cylinders while you're working.  I had to unbolt that brake line manifold down at the bottom too.  It's tough the 1st time but if I ever have to do another one I'll know the tricks.

 

Looks like rockauto doesn't have them now, here's the part I bought.  https://www.google.com/search?q=A1+Cardone+Remanufactured+Power+Brake+Boosters+53-5246&rlz=1C1BOFA_enUS494US494&oq=A1+Cardone+Remanufactured+Power+Brake+Boosters+53-5246&aqs=chrome..69i57j69i60&sourceid=chrome&es_sm=93&ie=UTF-8

You'll want to paint it black as it comes raw metal grey.

Just bought one off e-bay, an A1 Cardone rebuilt, part #53-5245,  $120.00 bucks including core charge with freight.  The add said it was their last one,  finding inexpensive small brake boosters for early cars could become an issue as time go's on although there were a number of Centric rebuilt units listed for around $200.00. 

I bought one for my '72 from Motorsport Auto  this fall. Couldn't find one at Rockauto eather. Core charge was steep at $300, but they refunded quickly when I sent mine to them. Very happy, no problems with bolt pattern.

The booster arrived today and it's correct so everything looks good.  I have a month to get the $30.00 core refund so with return freight I will be about $100.00 bucks all in...I'm a very happy guy. 

Great news.  I tried to remove the original sticker and glue it back on the reconditioned one but it wouldn't come off as a whole piece.  So now it's just black.  My rebuilt one didn't need any push rod adjustment at all, it was still at the right length. 

 

Have fun installing it, for me it was almost a PITA.