Distributors are amazing considering how old they are.  I remember years ago when a local speed shop offered to curve your distributor for $10.  The guy doing the work said he could give anyone a 10th of second ET decrease for $10.  $10s a tenth is what he said.  My smart ass buddy walked up and said he would take $100s worth.  We thought it was funny, the distributor guy didn't. 

Where do you find NOS points?

STANDARD OR ECHLIN.  Make sure the box says "Made in USA".

Likely, few are aware that there is also a wide variation in spring tension specs., even with NOS USA points. Too much, and the rubbing block wears down quickly, changing the timing/gap. Too little, and the contacts float at high rpms. Had to test quite a few sets to find good ones.

6 VOLTS/POS. GRD. NW INDIANA

Right, the spring is adjustable. That's why there are actually two 5/16 nuts, where the coil & condenser wire attach. The innermost nut is loosened and spring can be moved fore and aft as required, then re-tightened to achieve the correct spring tension. On Fords the specification for V8 is 17 to 22 ounces, checked with a spring scale.

That famous auction site usually has a good supply up for bid or BIN. Figure about $10 per, delivered to your door, is about par for the course. I see a good supply available under the old part number as well. Used from 1945 to 1974, so even today they are not rare or expensive. No reason whatsoever to use crappy ignition parts!

"Older part#: FAA-12171-A (replaced 7RA-12171) .. Point Set-Heavy Duty / 1948/52 337 / 1948/53 239 / 1948/64 I-6's ... In 1969, Ford replaced FAA-12171-A with C9AZ-12171-B (Motorcraft DP-3) which has many more applications too numerous to list."

Also consider the rotor, the earlier black rotors were pre-emission era. The later blue ones will work, but have imo an excessive gap, and they don't tend to last quite as long.

Don’t know about the ‘57+/centrifical parts, but with Loadomatic points, often no amount of adjustment will bring the spring tension into the spec. range.

6 VOLTS/POS. GRD. NW INDIANA

Interesting. I've read drag racers had all kinds of tricks and modifications (doubling up the spring say,) to prevent point bounce at very high RPM. The rubbing block lasted few miles this way, but it did work.

You can get decent parts, condensers included at your NAPA store, there are others also but ... few if any condensers are made in America anymore but that could change .... we hope.
I also had a new one fail on a trip to New York from Minnesota in our '54 Ford all original car.   I like you put my old spare in at a truck stop, it's still there and working well, might be an old original from those years....
Always carry a spare.   Another good idea is to replace the holding screw with an Allen head screw, # 8 is what most are, then you can control the screw far easier while replacing the condenser, far less chance of dropping or losing.   I made an Allen wrench attached to a screwdriver handle, this works super well.
warren

My dual points kit requires the condenser be installed on the outside of the distributor (mounted on the vacuum diaphragm) so replacement couldn’t be simpler. Just curious though, how/if that might extend it’s life (assuming temp. inside the distributor is higher, and the original style condenser’s electrolytic construction is susceptible to overheating damage)? I’m guessing the dist. cap must hold in the heat conducted up through the aluminum distributor body, which is in direct contact with the engine block. Although, if that WAS the case, likely the manufacturers would have designed the original ignition system differently, unless exposure to oil/dirt/oxygen/etc. was thought to be worse (?).

6 VOLTS/POS. GRD. NW INDIANA