I am going down the same path as you are, Eagle heads on a pre Eagle shortblock. I got my heads from a pull-a-part for $140 for the pair with rocker gear. They are not hard to pull. Most of the time the exhaust is cut from them from removing the cats so all the work is from the top of the engine bay.
As Dion mentioned the heads are nice BUT you will need a 70 thous thick head gasket to keep the compression down unless this is a race engine. If you have to shave the heads to clean up the sealing surface that will make the compression go up more. That being said you really need to buy two pushrod checking tools to get the lifter preload correct or you may be bending things as there is no adjustment. On the springs Mopar sells a spring that drops in and uses the Eagle retainer and is good to .625 lift. Part #68277306AA. Google it and find the best deal. Normally ~$80 bucks for 16 shipped. Also your pre Eagle intake manifold will not work.
You really need the spring numbers to see if they will work with the cam you are using. Are the lifters Mopar brand non-mds lifters? From everything I read they are the best.