This is a little big on duration, but it'll work.
http://www.summitracing.com/parts/CRO-31321/
Are you racing it more than street? If so, you can use that one. The KB167s will be an added plus. They would bring compression right on up. Do your stock pistons have valve reliefs? If so, you can play around with the deck height and thinner head gaskets and milling some off the heads. You need compression up around 9.5 with that camshaft so it will run well on motor. I wouldn't go over that though and I'd run a GOOD head gasket. Remember to, with magnum heads, comes the 1.6 rockers. That will be .563 lift on the exhaust side of that cam. BUT, the pushrod angle of the small block will knock some of that off. I think generally, it's about .020". Go to the Hughes engines site and click on the magnum section and look for your springs retainers and locks there. That's where I got my stuff. That's a pretty big cam for a teen, but if you're doing mostly racin, it's a dang goodun. It'll make great power with nitrous and run very well on motor if you give it enough static compression, converter and gear.
Oh and don't forget about shortening the guides if you go with that cam too.