Save the date in Spanish

I just did a quick google search and found many options.

I typed in "reserva la fecha"

also there's websites where you can edit what it says . . you could just type it in spanish.

I would try Etsy if you haven't already. I looked and there appear to be many options, plus most vendors there will customize the language on their templates to whatever you specify.

Lots of the places have a option to provide your own artwork. You could have it typeset in Spanish and upload that.

I recommend trying Etsy! They usually offer customizations

Zazzle and Etsy have some STD's and invitations in spanish

I ordered my invites from PenelopesPaperPantry on Etsy and they do invites in Spanish. Their products are beautiful and they have so many great reviews! Plus they are doing a big sale until the end of January! Another option is online websites like Basic Invite. We ordered save the dates from them and they are completely customizable so you could type them in Spanish yourself. They also offer free address printing on the envelopes. Definitely order some samples before you order your save the dates though because they offer a lot of different paper types, and for me it was difficult to know which ones to pick without seeing them. They have a ton of different template options too. Hope this helps!

Zazzle, Etsy, design your own on canva.com