I doubt if Horizon is recruiting outside of the USA...yet, They are just a little better than the average regional here in the US and I believe they have a quasi flow through to Alaska Airlines which is a very desirable airline here in the US.
Skywest is not bad and while the wages are not stellar they are better than mst of the other regionals. They do have a base in Seattle as well if that's important, A friend of mine got an unsolicited card from Skywest urging him to apply for a position so they must be on an active hiring campaign.
Most if not all major airlines here in the US will not consider you without a four year degree. That may change but I would not hold my breath waiting for that to happen.