i want to change the rims on my 70 duster. It has the original ralleye wheels. I am having some trouble finding wheels with the small 4 in. bolt pattern. If anyone has answers it would be appreaciated.

Centerline has autodrags in the 4" bp.

Cragar has the ss rims but only in 14".

Summit has the rallyes from wheel vintiques in 15".

wheel vintuques also has those ultra cool billet 18" ralleyes

The above is correct but you can get Cragar SS 4" bolt pattern in a 15" Wheel.  Just bought a set.  Google Newstalgia wheel.  Ran me around 165.00 a piece for 15x8's and 15x6's.  

Take the time and money to switch to large pattern with disc brakes in ft, and switch rear end to a large pattern 8.25. You can find those easy and cheap. Then you can get any wheels you want. I did that, And I love it. Don't waste your money on small pattern wheels, cause you will likely want to upgrade those other parts later.  

I agree 4" rims are not the way to go. Upgrade to the 4 1/2" pattern, the selection of rims alone should convince you to go this way.
If your going to change rear ends go with an 8 3/4 with a posi, the 8.25 is border line at best behind a strong 340.
If you don't want to change rear ends, pull your axles and send them to your local machine shop, they can re-drill the axles to the 4 1/2" pattern, I know someone that did this in a 9 second Duster and had zero problems.
For the front hubs you can probably upgrade to a later model rotor, e.g. Volare with a 4 1/2" pattern, just double check to make sure the bearings are the same size otherwise you will have to change the spindles.  
Good Luck  

check out wheels for less.com.  They have the new version of the aluminum Ansen Sprint five slot wheels. They come in small bolt pattern in 15x7 and 17x7.  I was thinking about these for my Scamp until I changed to big bolt pattern. I have Magnum 500's on for now until I Minitub later on.  The only bad thing about the Ansen Sprint wheels is that they look so 70's that I think you'll have to grow sideburns.