The closest is Disney's Grand Californian, which trades in RCI, but 1 year in advance is almost definitely not far enough in advance to get an exchange there. I've only got one, and I started that search almost 2 years in advance with a wide range of dates. Absolutely incredible, though.
Another nice one, but a bit distant, is Marriott's Newport Coast Villas, which trades in II. It's pretty easy to get into off-season (I got two exchanges with a really low value trader), but a summer week might be tough. You might need Marriott preference for that. The distance really depends on traffic. With no traffic, it's less than half an hour. If the traffic is bad, it can be an hour.
Dolphin's Cove is probably the best choice that you can get. It's less than a mile away. I would consider it a pretty "average" timeshare. Nothing special (except its proximity to Disneyland), and no real negatives. I think it's in both RCI and II.
There's also a nearby Worldmark in RCI. I haven't heard much about that, and wonder if that's because it's hard to get?
Peacock Suites (exchanges through RCI) is another close one, but I've avoided that one because the reviews say that the units are small and only have partial kitchens.