Why are you limiting yourself to the GM hot cam.
You can reach and exceed your power goals on a 350 with warmed over vortec heads, a dual plane vortec rpm intake, 750cfm carb and 1-5/8" headers using Edelbrocks "Performer RPM" hydraulic roller cam and Comp cams beehive springs.
You can drill and roll pin the rocker studs and shorten and reduce the valve guide bosses yourself at home using valve seal install tooling you can buy from the cam companies in a good 3/8" drill. Comp beehive springs do not require machining the stock spring seat inner diameter and provide superior valvetrain control without excessive spring pressure.
You can tune up the port flow on the vortecs for more power, yourself. The intake ports are very good as is. No big reshaping is required. The intake side only needs cleaning up, smoothing and valve guide boss contouring. Stay away from the valve job. Its very efficient as is. The exhaust side responds well to a full port effort. The stock valve size is fine.
the Edelbrock performer RPM hyd roller cam is available in a "retrofit" version and a OEM roller block version using OEM roller lifters.
This is the same cam used in their 350ci E-tec crate motor. 1.5:1 rockers are fine.