There is only one blend that I will pay a premium for when aged 14 plus years and even then if it is over a certain price I will pass. If I were looking for hard to find tobacco blends today I would do what I did back in the day. I would call around the low tax states for small mom and pop stores with little to no internet presence and see what they had. I got almost all of my Esoterica Stonehaven and bulk Samuel Gawith Best Brown, Full Virginia and St James flakes this way back in 2012. I had a guy giving me 10% off on all the SG flakes when I was buying in 5 pound lots. I believe I was paying 52 and change for a pound back then with my discount.
There are plenty of great blends that are readily available today and smoke very nicely even fresh. I would be loading up on Capstan Blue Flake, Solani 660 Silver Flake and 633, Mac Baren Old Dark Fired, Escudo, Peterson Deluxe Navy Rolls and Flake(the old Dunhill blends). I would also be buying Peterson Irish Flake, University Flake, 3P's. Here are a few others I would be buying if I were building my cellar today.
Savinelli Doblone d'Oro
Orlik Dark Strong Kentucky
Dan Tobacco Salty Dogs
GL Pease Navigator...needs a few years but worth the wait.