Hi! This is right up my alley as I am working on a charm bracelet myself! May I suggest vintage charms? My bracelet I am working on, the bracelet itself is new, I bought a few years ago, but all the charms I am putting on it are vintage, mainly 50's-60's.
I am a vintage "freak" to begin with but also I feel that the vintage charms are much nicer, better made and more detailed, and huge variety.
I get mine on ebay, they have the widest variety at the best prices, etsy has some too but not as much and not as good a price. You can get them in solid gold - usually they are 14k but also some are 18 or 10k as well as the vtg British ones in 9ct and you can also get them in sterling silver.
Prices vary, of course silver is much cheaper, but some can be a little more due to the charm style- some actually move and do things, I am doing a gold bracelet, and I have found the charms start around 50 to 100 for small charms, esp in 9ct. and average are 150 and up (to 1,000 and more!)for most charms.
My first one I started with I wanted to be the centerpiece and be special, I had been watching it for quite a while, it's a 14K Large 1 1/2 inch disc with scalloped frame and it has a 3D Poodle (love!) on it and has 2 rubies for the eyes and 2 more rubies and 1 sapphire around it, it is heavy at 13g and cost $430.00, but was worth it, and actually was a good deal, it's so pretty and I love the 1950's poodle theme. Another I have is a gold basket of real pearls, very sweet!
Many of them have the real gemstones and pearls, and that adds to the price, as well of course as the weight of the gold or silver. But you can get them at various price ranges from low to high.
There are a few online shops I have seen that also offer vintage charms but their prices are usually higher than ebay. You just of course as anytime buying on ebay, want to make sure they describe if there are any flaws, etc. But the charms I have got were all in great condition, they looked brand new!
I am sure some others may know more about new charms and where you can find some, but I figured I'd give a shout out for the vintage ones!
Sorry so long, but I sure can ramble about this, I have been obsessed with vintage charm bracelets for a while now, lol!
Good Luck and have fun searching!