The drop in link bar lifters will allow you to use any off the shelf roller cam. Cost is around $400 just for the lifters. Changing the dist gear would also be necessary with a roller cam.
You can use the Ford factory "spider & dog-bone" setup, but in an early block that would entail a
small base circle cam which will limit your options on specs.
Having said that, for
your described application, I just don't consider the gains to outweigh the cost all other things being equal. I thought about doing a roller cam in a early Mexican 302 block that I used for a 331 stroker. After doing the research, I went with a (relatively mild) custom spec'd hyd flat tappet. Ended up with 330hp to the wheels in a '65 Fastback with a C-4. I'm presently building a 408 with a solid flat.
Vizard recently did testing on a Spintron and dyno comparing similar flat tappet to roller cams (both solid and hyd in both cases). He found that until you exceed 270* duration on your cam, the flat tappet outperforms. From 270* to 280* or so their about even and from 280* on up the roller edges the flat tappet.
If it were me, I'd do some nice home porting/gasket matching of the W heads and maybe have them milled depending upon your current c/r, piston style, piston to deck height, etc.
I would then consider the Comp XE262H or the XE268H depending on my desired performance level. I had the 262 in a mild 302 and it worked great, IMO.
Just my opinions....others may differ.
Good luck whatever you decide.
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