Re: How much?
Yes, cheaper than the Motorola part and Intel's CPUs.
The original 6502 was pin compatible with the Motorola it was a "clone" of. But due to an employee of MOS stupidly having a reference manual from Motorola (they all used to work for Motorola) it was deemed to be infringing on Motorola's IP.
The pin layout was changed, that's about all.