Jaguar Mark IX Brake Pads

I was hoping someone could recommend some options related to available brake pads for the Mark IX. When I do a Google search I get conflicting information.
I’m needing to replace the fronts. I replaced the rear with BrakeBest D23.Purchased at O’Reilys. The box also has BB1384 written on it. When I called the store they said the D23 was for Front Only! Does that mean the ones I installed in the rear are incorrect? They’ve been on the car for 2 years!
Hence, my confusion…
Any advice is appreciated…

It should not be considered unusual for discount parts places to have wrong information in their computers for our old cars. Not long ago I ordered something for my Mark V from Rock Auto and they only had it listed for model year 1948, even though Mark V was made from 1949-51 and all of them used the part.
The Mark IX factory parts catalogue shows one part number for front pads and another part number for rear pads.
Fronts are usually larger than rears, so I wouldn’t think it possible to install fronts in the rear.
I would trust some of the Jaguar specific parts vendors such as XKs Unlimited. This is their front set at $89.
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Thank you, Rob! I’ll look into that…