Are these really rare?

[7E-Bodies]

OK, so I was told I got extremely lucky in finding these. My 70 RT was originally equipped with 11 inch front disc and that's what these are. According to what I found they're supposed to have 1.000" thickness and these might have .010" wear with no grooves. I actually heard one guy saying they were worth $1000 a pair these days. If this is even remotely true, should I set these aside as future trading stock or put them on this front end that I am meticulously building to be a stock and original (looking) as possible? I get it... The ball joints aren't original, nor the idler arm, nor the knuckles, nor the imitation cosmolene LCAs, nor the UCAs, nor the powder coat on the K frame, nor the shocks (that will be painted like originals) and the original steering gear box is at Firm Feel as I post this. So bottom line question, should I save these relics and just order aftermarket discs? Or should I go with the original since this car will not be driven too much? Take it easy on me here, I have zero experience on front ends and I'm learning this process as I go and as I look back through previous threads and learn from you guys. Also know that this is just a Fingertight assembly as I verify parts and what not. I'll be looking forward to hearing remarks and advice on these rotors.

[7E-Bodies]

And yes, I have the correct calipers, all rebuilt/restored by brake warehouse in Minneapolis. Even a fully restored 2229171 MC and the car's original and restored (Booster Dewey) PBB.

[mtull]

I actually heard one guy saying they were worth $1000 a pair these days.

I've seen a few sets of NOS Kelsey Hayes rotors with left and right hand threads for sale for 2K plus in the last two years, the sellers still have them.  I'd guess Kelsey Hayes two piece rotors would go for more than centric or similar two piece aftermarket rotors of the day assuming they were close to the same thickness and had the original wheel studs.  I'm by no means a well traveled swap meet guy but can say rarely see them.  I can't tell from your pics, do they have the left hand threads and what brand are they?

I recently bought a pair of Kelsey Hayes two-piece rotor for next to nothing but I got really lucky.

[blown motor]

What does your gut tell you? Does it go sideways because some part isn't original or NOS. I take it the answer is no based on your ball joints, idler arms, LCAs, UCAs, etc. Does having one more part that's an original from back then make you feel better? There's your answer.

[440ehigh]

If you've had everything else that's original restored and don't plan on driving the car much don't see why not using the rotors if they are still thick enough.
As everyone said original 2 piece rotors are hard to come by especially if the thickness is close to the same for both.

I've found one that's still has full thickness but no luck finding another one that's close to the same thickness.

Sometimes you get lucky like MUTLL and still find them.