$500 for 500 patterns is not that unreasonable when you stop to think that this person spend roughly about $1.00 on each for: envelope, paper, toner ink, time to find the patterns and then took the trouble of keeping them safe.
The only problem is, in our "computer age of time" we all know that we can get these for free on the internet, or almost free, we still would have to spend money on printing them as we needed to. So all in all I don't see the problem with the amount that is being asked.
If we didn't have the computer availability like we do, we'd all probably jump at the chance of having them.
Just MHO