Looking for less expensive alternative to San Sebastian

Hi all,

My wife and I are looking to relocate to Portugal or Spain; if it is Spain, we really like the San Sebastian area. The major factor differentiating the Algarve region in Portugal from San Sebastian is the cost of living.

We are relatively young (33), working for American companies - My wife's job wouldn't change (online) but I would take an income hit moving to Europe (I am a teacher and would take a teaching job online instead) but it's worth it, in our opinion. We COULD make it work in San Sebastian, but we'd have more flexibility if we could pay in the 500-600 euro/month (or less!) range for an apartment (1 BR/Studio is OK) range.

Are there any towns near San Sebastian (within 30-60 mins) that are worth a look? Beach towns preferred, I love surfing, and honestly, I'd love to spend more of my life surfing and less of it working. Love teaching and interacting with kids but I've put 10 years into the system and ready to retire 

BTW I am a US/EU dual citizen.

Thanks!