Tough Question. We are definitely under-served for our population in St. Louis when it comes to pipes.
Of those listed above, you'll find the best tin and pipe selection at Jon's Pipe Shop in Clayton. They are full-on retail, so be prepared for that when you compare their prices to what you see online for tobacco.
Dangler's has been a dissapointment for a number of years now. T & C tries, but they are primarily a cigar shop. Don't expect much in the way of help from their workers when it comes to knowledge about pipes and tobaccos.
Oh, and there is a new place in Soulard (near downtown, but south) that sells pipe stuff as well, but I haven't been there. I've heard OK things.