Small block or big block in a truck?

I'm starting to plan for my next project even before I've got this one out of the garage and on the road. I'm liquidating a bunch of stuff and trying to decide what stays and what goes.
I recently procured an 84 short bed 2wd Dodge pick up with a slant and an OD 4spd. I'll be driving it as is powertrain wise while I fix the body and interior and get the suspension to my liking. I plan to build it as a tribute to my favorite truck I ever owned which I totalled off when I was 19.
The dilemma is this. I have all the parts to drop a 400 and a 727 in it, also I have all the parts to drop a 360 and a 727 in it. Just not sure which way to go. It will be a 2.94 geared Cruiser.
Is a small block cheaper to build than a big block? Pros and cons to both? I know there are a few more options in the head market for the bug block. I have no real experience with big blocks but I am curious!

Cley
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