I think you're best bet is networking. As you say, you're a social enough person - go to industry gatherings in your locale - so that you are narrowing down your search to the local area at the outset. Then gently nose around for working environments that work for you - see who you meet that has an office themselves or knows of companies that offer this, and target your search in that direction. The bonus is, you also develop a personal network that helps get you in through recommendations as opposed to posting to open positions with the masses.
The other thing I can think of is to try to diagnose what strategies lead to companies finding it a worth while expense to give people offices. Offices are more expensive than cubicles - most places pay per square foot, and offices simply take more space, plus the work to build more walls and plan out air flow - a one time cost, but it has to amortize over a certain number of years.
One would like to think that every company puts a priority on people having the ability to focus, but clearly there are other tradeoffs that favor open floor plans and I don't think anyone's really made a definitive case for every circumstance. One thing I see is that - with a wide sweeping brush:
Offices connote status - companies that want to show that a given role has a high status will get that role an office. This is a factor not only of the need for showing status, but also the need to show status to people who are visiting in person.
Roles with confidential information sharing where the whole team does not have a need to know. You'll see it with some info sec, and lots of manager roles.
Roles that involve work that is annoying to others - for example, the one guy who takes phone meetings all day may get locked up away from everyone else, because it's easier to wall him off than to give everyone else offices. Similarly, I've seen guys with really loud machinery (white noise but still loud) get private spaces, more like labs than offices, because of the noise of their tools. If what bothers you is human voices vs. white noise, working in a private lab may be an option.
All of these are cases where your need for an office is less likely to change. One trick is that moving into a team that offers offices for no obvious reason other than "we've had lots of offices in this building so it just worked out" - means that your office is as likely to remain only as long as the lease remains. If there's a driving reason for you to have that office, it's more predictable that it will stay around.