Hi Willson,
I'm going to second the Maria cookies recommendation. They have long been the expat community's replacement for graham crackers in recipes.
I would make "magic cookie bars" while in Spain, and use Maria cookies for the graham cracker crust, and chop up chocolate bars for the chocolate chips. It took a little longer to make, but the reactions I'd get from our Spanish family and friends were so worth it! (They're called "magic" because they disappear so fast!)
Good luck! In my years in Spain I found that Spaniards love American baked goods; they're quite different from what you can buy in the pastelerias, and they appeal to anyone with a sweet tooth! I know of two American women who baked and sold desserts very successfully, one in a shop, and another in a restaurant.