I don't know about the cam on E-Bay as no manufacturer or warranty is mentioned. As for the other, it is most likely a stock regrind for OEM replacement.
You need to speak with specific cam manuafacturers about their ability/willingness to grind a cam for you. They will get together with you to discuss how far you want to go and how much you are willing to spend. A lot also depends if anyone has any new blanks available. If not, a regrind of a stock cam is the only option.
Use a search engine for ISKY, CRANE, COMPETITION CAMS and CROWER for a start. MEL came through with hydraulic tappet cams so any type of upgrade is going to cause a resultant upgrade in the valvetrain. It all needs to be planned out.
Click on URL;
http://www.egge.com/