The thing that makes Noodler's ink attractive to me is 1) they have a wider variety of colors than most brands, 2) more of their colors offer water resistance than other brands, and the water resistance on those is usually stronger and 3) it's one of the best ink bargains available in the USA. If being abroad and not having a cheap source negates #3, then it's just a question of whether #1 and #2 come into play enough for it to be worth the cost. I think Goulet and Vanness both ship internationally, and both offer sample sizes of Noodler's inks. I would suggest you order a bunch of Noodler's samples of inks that appeal to you and then see if you like any of them enough to justify the extra cost of import. Just note that Noodler's has a very experimental, out-of-the-box approach to formulating inks, and that's both good and bad. Good when inks have unique qualities that you want and can't get elsewhere, but bad when you get an ink that doesn't play nicely with all pens. Do your research about a particular color before putting it in any vintage or expensive pens that you prize (this is a good thing to do with any ink from a small, "boutique" maker).
As for the pens, you'll get a lot of differing opinions. I have an Ahab (it was my second fountain pen), and I have always liked it. But I'm a tinkerer, so I enjoyed the fact that I can tweak the pen to write/flow as I want it to. The downside is that the pens often NEED that extra work (heat setting the feed, adjusting the nib, etc.) in order to write well at all, so these are definitely NOT pens for people who want a pen that will just write well out of the box. If you're just looking for a steel flex nib at a bargain price, I would recommend FPR pens (their house brand pens). Their flex nibs are better than Noodler's nibs, IMO, and the pens tend to work well right away. I have an FPR Himalaya with a flex nib upgrade, and I think it's a great pen for the price. I also bought a #6 flex nib from FPR and replaced my Noodler's nib in my Ahab with it and found it great. The downside to FPR is that they don't have nearly as many color and material options as Noodler's pens.
As for American pens in general, there are a number of pen turners who are well known here who make coveted custom pens, but if you mean "brands", you should check out Edison, Franklin-Christoph, and Karas Kustoms. These are American made pens with excellent reputations for quality.
Monteverde and Conklin are both Yafa brands. Yafa is an international conglomerate. Parts for these pens may be sourced from different companies in the conglomerate and also sometimes from China. Be aware that the modern Conklin is a resurrected brand, i.e., the current Conklin pens have no real continuity with the vintage Conklin pen brand. The current owner bought rights to the brand. Both brands seem to have quality control issues from time to time. If you're interested in these pens, you should monitor reviews and feedback on the Internet to see what the QC is like at the time of purchase.
Sorry this ran long, Hope it's helpful.