In the internet age, you have more opportunities than ever to find that perfect pair of vintage frames. Vintage glasses are easier than ever to find because of online auction sites and specialty retailers. The drawback is that prices have gone up in recent years compared to what prices used to be: now, it seems that everyone knows what vintage glasses are worth.
But those rare and hard-to-find eyeglasses are still affordable; you can pick up even a pristine pair of vintage Shuron (or SRO, Artcraft, or American Optical) glasses for under $100. That's usually less than you would pay for a new pair of designer frames - but vintage glasses have the added value of some history behind them.
What to look for when buying vintage Shurons is very simple - you can tell with a quick glance (or a few good pictures) if you want a pair of vintage frames or not. Here's what to spot-check:
Some parts can be replaced or repaired, but there are so many frames available today at both online sources and traditional sources that it's often better to wait - and find a pair of frames in good condition.
Surprisingly, you can find frames in brand-new condition that were originally manufactured as far back as the 1940's and 1950's. These old glasses have survived for a few reasons: Shurons have always been of very high quality, and their great durability lends itself to them looking like new - even after many years. Another reason is that some people might have had more than one pair, or they had a pair that looked more formal - which they rarely wore. Finally, some optometrists have had forgotten, unsold pairs that survived without ever being sold or worn. (A friend of mine had a never-worn pair of Clubman-style glasses he got from a small-town, family-owned optometrist - the glasses looked like new but were around 45 years old!)
If searching for these types of frames, search auction sites for terms such as "new old stock", "NOS", "dead stock" or "deadstock" in combination with the brand and model of frames you want to find (like, "shuron ronsir" for instance) . These terms will find you the ones that have never been worn. (Also, try terms such as "like new" and "never worn".)
Another tip when searching for glasses is to use unconventional terms when describing which frames you're looking for. Many sellers don't know the actual model or brand name - so they make up words to describe the eyeglasses they're selling. Try searching for "g-man", "nerd glasses", "buddy holly glasses", "vintage glasses", and "rockabilly glasses" and you'll be surprised how many great glasses are being sold without full, proper descriptions - that you can buy!
Lastly, don't neglect the more traditional off-line sources for vintage frames. These would be estate sales (my favorite!) and antique malls. You can find tons of glasses (cheap) at estate sales because most people don't see the value in "old glasses" unless they're extremely old and ornate, gold-filled, or have an obvious and recognizable designer name (such as Persol). The vintage "nerd" glasses are low on the list, so at large estate sales you can usually get a pile of classic frames for just a few bucks.