Woudl a Holley model: 80457 600cfm work for the Offy dp application? Its got everything I need, electric choke, kickdown.

They're about $200 less than the 390.

 

Model 1850/600 cfm probably less expensive and readily available on eBay (holleyperformance) and jetted leaner (#66)than the 80457(#69) and is available with electric choke and can probably be fitted with whatever kickdown linkage you need. The 8007/390 cfm might be better for your application. Call or Email the Holley Tech's for advice and info. Contact info available on the Holley website.