Whether or not it comes with fans is anybody's guess. It will tell you if it does or not. You can mount any fan on any radiator. The only difference from radiator to radiator to fan to fan will be the degree of difficulty in mounting them.
The RBX is slightly larger, and has 3 barbs instead of two. It covers a little bit more surface area, but will only give you cooler temps by about 1-2C. Plus, you will have to get a larger pump to make up for the flow restrction from the third barb. It is also a little bit more expensive. Not worth it IMO.
That radiator is 120mm, therefore a 120mm fan would mount great on it. You would have to get or make a shroud for it to be perfect, and maximize performance from it.
The radiator is the same as the 86 Chevette heatercore, just with a few mods done to it.
Go there, Weapon is THE GUY at XS when it comes to watercoolign. He mods the hell out of his rads, and makes his own shrouds. Makes some very quality stuff.