I'm doing a 408 stroker build right now, here are the parts:

1) '74 360 block, 0.030" over
2) Eagle forged crank
3) Eagle H-beam rods
4) W2 Econo Race heads (cast-in rocker shaft pedestal, but using the long valves)
5) Mahle PowerPak pistons (4032 alloy), should give me a 10.5 static CR
6) Edelbrock Victor 2920 single plane intake
7) Comp Cams Hudraulic Roller XR292HR-12, so actually a 112 LSA since car is about 95% streeet ride
8) TTI 1-7/8" headers (these go into a full lenght 3" X-pipe setup)
9) Harland Sharp roller rockers, 1.6 ratio

That is going into my coupe, 3600 lbs, 4K stall converter, 4.10 gear out back. Would love that combo to dip into the 11s, but I have no traction, so low 12s will make me happy.

Leaving out a pile of normal parts such as gaskets, timing chains, bolts, etc. I am about $8.5K total spend, with $3K in machining costs and the rest being the parts.

The big cost NEW parts for me where:
1) roller setup => cam and lifters
2) W2 stuff => rocker arms, intake and headers

...so that's a good chunk of money right there that I had to spend because I couldn't re-use my old LA stuff.

So there is a ballpark figure of what that costs may be like for you. If you are not departing the factor-like setup, so no W2, etc. you will save a pile there!