A "merchant gateway" is simply a plugin straight into your banks systems, effectivly cutting out the middle man like 2checkout. At the end of the day, you can only get one if your bank offers you this facility.
The hype around them is because until only recently only the US banks really gave them out to people. However, European banks are now starting to catch up on this and are offering their own implementations.
The problem is that I don't think any bank offers merchant gateways to companies that A) Aren't registered in the same country and B) don't have a proven credit record with them.
So, I suggest you speak to some of your local banks, see if they have, or know of, a gateway. If not, maybe you should consider setting up a branch office in an EU country, although that of course brings with it all the issues of tax, residence, etc.
Anyway, good luck!