I deal with Engle's Coin Shop Engle's Coin Shop Inc. - Home They are very fair whether buying or selling.
I have bought quite a bit there as well. I can't say that I find him terribly cheap but I don't feel like I'm being ripped off. They do keep a good amount in stock, though, I can say that for him. Many places you call these days have less than 20 eagles in the whole store.
To the original poster, I think you need to ask yourself why you think you might need the physical silver, that will lend itself to some direction as to what type you should buy:
1. Are you going to get into collecting? Then get graded coins and some of the nice, small coins from Europe.
2. Do you want it strictly for investment purposes? Then stick to lower premium bullion--like large silver bars or 1 oz or larger gold bars. And bullion coins, when you can get lower premiums.
3. Do you want them for bartering after SHTF? Then buy mostly junk silver and/or clearly recognizable silver bars/rounds/coins that clearly indicate value, fineness, etc. Junk (pre-65) is generally the recommended type in this scenario, although I'm not convinced totally myself.
4. Got a mix of several of the above scenarios? Then buy accordingly.
Good luck. Whatever you do, buy a LOT and keep driving that price up