Why do you think you will need a custom camshaft?

I think for a start I would contact someone like this for a recommendation for an off the shelf camshaft and supporting hardware if needed:

Modern Muscle Performance
340 Colonel Lee Road
Martinsville, VA 24112
Phone: 276-666-1934

Please use the email address below for sales and technical questions!

E-Mail: info@modernmuscleperformance.com

Hours of Operations (Eastern Standard Time):
Monday: 8:00 AM to 5:00 PM
Tuesday: 8:00 AM to 5:00 PM
Wednesday: 8:00 AM to 5:00 PM
Thursday: 8:00 AM to 5:00 PM
Friday: 8:00 AM to 5:00 PM
Saturday: By Appointment Only
Sunday: Closed