Hello and welcome,
Since this is a classic forum, you've been given classic answers.
As myself always trying to catch-up (when possible), I can bring on MiniMig here. That's just a tiny remake of A500+. It has no keyboard, only an SD slot for games and other ports for input and output. It is pretty inexpensive (as for new Amiga hardware!!!) - below 200 Eur I guess. So this is if you wanted to have a device that reimplements ECS and is brand new.
Also if you own a Windows Mobile Classic or Pro device, try PocketUAE. If not, if you're a happy s60 Nokia owner, check out UAE4ALL (see the link below). These all are UAEs working on cell phones or WM palmtops.
Hope this helps to widen the scope.