Going for this look, what size tire should I go with?

I’m looking for the bone stock look for rubber on my 15” ralleys. What size tire would you recommend?

Or like this one

i think the comparison to a g series tires used in the old days is p225/70/15 or maybe 235/70/15

Well, "bone stock" on B-body 15" Rallye-wheel cars was F60-15; that's about 235/60R15 in modern-radial size.

Great thanks guys

probably these tires, guess which size though, looks like 70 series, so i'd guess the FR70-15

https://www.cokertire.com/tires/styles/classic-70s/firestone-wide-oval-radial-rwl.html

15 inch rallyes on a 70 B-body would be 235X60X15 as stated above. No 70 series on a 15X7 on a B-body.

I like the look of the 225/70R15 on the B-body's. A little taller than stock, but fills the wheel openings nice.