What's it cost to re-core and add a core?

I paid $550 to have my 67 stock 2 row 1/2" to a 3 row 7/16" using both stock tanks.
Best deal and choice is this exactly..Radiator shops are ever fewer as time goes by.

I did a top tank removal and rodding out about 5 years ago. Myself.But I enjoy challenges in soldering.