You want a coated stock vs a dull stock. The coated stock will hold the saturation and detail much better.

As sledger, ask your printer for his recommendation. Printers have stock they have purchased and if you can use these without the printer having to order stock you are better off.

There are also some on-line printers who do what is called "gang printing" where they put several cards on on one plate and print all these cards at once. This is a much more affordable way to print but a method that does not do anything to help your austerity program