Wheel Vintiques Steel Wheels ?s

I want to put body colored steel wheels (with red-line dog dish caps) on my '71 Dart GT. It looks like I'm "forced" to go with 15" diameter. SummitRacing sells Wheel Vintiques 15" X 6" (3.75" back space) and 15" X 7" (4.25" back space).

My car has the factory installed 5 on 4" small bolt pattern 8 3/4" rear end (3.23:1 sure-grip). The front suspension was rebuilt, with Moog parts, and I added the SSBC front disc brakes (which allows me to keep my 5 on 4" small bolt wheel pattern (1 spare tire)). It also has factory 14" X 5 1/2" (3.75 back space) Rallyes on it currently.

Now my concerns/questions:

Should I go with 4 of the 15" X 6" wheels? Or, 2 of the 15" X 6" wheels & 2 of the 15" X 7" wheels (I do not want to mini-tub or re-locate rear springs).

If I go with 4 of the 15" X 6" wheels, should I get 4 of the same sized tires, or should I go with different (front vs. rear) sized tires?

How is Wheel Vintiques quality? Is Summit's price, ~$110 each, reasonable?

Any/all opinions welcome.