Stock Rim Size for a 60-66 K10

[argonaut]

Gents,
I'm trying to pick up a set of 16" steel wheels for my 66 k10. I intend to put skinny tires on, either a 235/85R16 radial or one of the old style bias play skinny and knobby .
Originally I thought I'd be looking for a set of 16x7" truck wheels, but perhaps they were thinner. I looked at a set of 16x5" (give or take) today. The guy said they were from a 40's - 50's car.... but the dimensions checked out for the bolt pattern and center bore. I'd like to pick these up if they are the correct wheels.

Can anyone help give me some insight as to what original wheels sizes were and what my options might be, or what to look for. I also need to make sure they'll work with front disks on my D44 front axle.

Thanks!