If he is talkng about JUST the baffle, then you are telling him too much. If it was the canister and baffle, it might get over $100. If by the picture he calls that "good" condition, I wouldn't pay $50 in that (fair) condition. I've seen plenty of new canister/baffle/packing in Competition size (2.5 inch) brushed finish go for $100-$150.
A baffle only, I'd be ecstatic to $50 used But what do I know, I've only been doing Vmaxes since 86.