I'm looking for stainless steel water storage options (304 preferred), 10 - 200 gallon range but not finding great options or retail outlets for such things.

Are there some common sources that SF uses?

Most water storage that large is plastic, but maybe look at modern stainless 10 gallon milk canisters.

I'm having internet issues right now, but here are some options:   IBCs - Intermediate Bulk Containers
http://www.ebay.com/itm/USED-FOOD-GRADE-275-gallon-IBC-Liquid-Storage-Totes-    
http://generalcontainer.com/product.aspx?pid=28    
and last but not least:
http://www.hooversolutions.com/products/ibcs/liquitote.html    
http://www.hooversolutions.com/products/ibcs/reconditioned-ibcs.html    
definitely the way to go if you have the cash.  I've worked with these things sporadically, they're impressive and come in all sizes.

and there is also the option of buying s/s 55 gallon drums; but the s/s IBC might be the better buy.

Great suggestion.

I like the idea of a stainless IBC tote.  Pricing is high, but not ridiculous.

Custom made marine stainless water tanks
http://coastlinemarinetanks.com/water-tanks/

http://www.speedytanks.com/

http://sunshinemarinetanks.com/