Beltway - otherwise known as Total Wine in Towson - more Loch Raven, actually - has Eagle Rare pretty regularly. Haven't looked for it in a while. Midway Liquors on Rt 40 has a ton and the owner is sensational at getting just about anything. He's either walking around the store or he's up in the raised corner manager's area overlooking his domain. You can check their websites.
Regarding 100 proof +, I always thought 90 proof was the sweet spot. Sometimes 100+ can be a little too "hot" and needs a rock or two. Overall, tho, I prefer neat despite that. But 90 is almost always perfect right out of the bottle. I went thru all kinds of bourbons over the years. Blanton's is excellent, but expensive. Four Roses Small Batch, in the heart-shaped bottle has become my regular for the past few years. I do like both Buffalo Trace and Makers Mark tho for a change. I gave up on trying boutique spirits. There are too many distilleries that cut corners and try to rush the aging process. I get why they do it, but most of them just aren't as refined as the old tried and true ones.
There used to be a lower end Van Winkle that was fabulous. I haven't seen it in years. Old Rip Van Winkle it was called. I also really like Weller. A buddy gave me a bottle a couple years ago that I tried to nurse, but it was too good and got killed after a rough week of teaching Middle School. It's been known to happen...