@gramboda We're in a similar position, hunting for similar watches. The wallet is willing, but the mind is overwhelmed!
I found it helpful to pore over the forums here related to the ref in question - you'll find past transactions, discussions of fakes, and evaluations of different used watches' conditions, all of which are very helpful in developing a frame of reference (Reddit is great for this as well, regardless of whether or not you would wish to purchase there).
I'm still hesitant to pull the trigger on anything, but I feel much more confident than I did before in my ability to spot a dog of a deal. Maybe tell yourself you will not buy anything for x-amount of time, and will instead just commit to trawling listings and developing said frame of reference.
I'm glad I let some of my early targets slide, and have discovered a sense of calm and patience from seeing new Seamasters pop up on Chrono and Ebay every day. My hesistance has allowed a couple of deals to slip through my fingers that I wish I would have acted on, but I know I'll see something similar come floating my way again if I give it time.
All that said, if you really like the new Seamasters, maybe just cut out the hassle and save for one. $2k is still a lot of money, so it should go toward something you will truly love, instead of something you'll merely settle for. I'm targeting an earlier Seamaster because I specifically like things about them that have since changed, but damn do I wish I could just save a little longer and buy one new, cutting out all the stress.