Is the seal just your standard round double lip seal?. The local agent wants $90 for one and for that sort of cash I'd be expecting something unusual.
The actual size of the seal Im not 100% sure of. Im sure someone here could measure the size of the crank. As for the seal itself, I wouldnt say its anything special at all, its actually only a single lip seal, an should be the same as 1.5's.
The most ideal way to replace it, would be to remove the old seal and find something the same from your supplier.
If you do find something, take note of the direction of the small grooves molded into the lip, they work to keep oil inside the engine, so go in a particular orientation to engine rotation, if it happens to be in the other direction, oil may leak out.
Josh.