Them Holley's are nice....but pricey!
They are pricey, but in their defense, they are a fantastic mix of economy and performance. Much like the Thermoquad with their very small primaries and big secondaries.
They are a viable alternative if you don't like the learning curve of the Thermoquad.
If it was me, I would get that thin Edelbrock spacer and run an Eddy 600.