I have a P1 on a card, perhaps that's worth a lot of money too?
Perhaps it is. If it's an SBC then it could be worth a fair amount, as supply is low and demand is moderate.
If, however, you're just trying to say that a P1 on an accelerator card is the same as an Amiga accelerator card, then I'd strongly suggest reading up on basic economics....
Supply of Amiga card = very low. Demand for Amiga card which is fastest CISC Amiga CPU - very high.
Supply of PC card = very high. Demand for PC card which is horrendously slow compared to fastest CPU - very low.
Now which of the above do you think is worth more money?
It's kind of like saying an Aston Martin DB4 is worth no money because it's slower than a Golf GTi (which it is, more or less). Try going to an Aston owner and offering him a grand for his DB4 and see the response.