What kinds of apples are suited to be filled with cranberries and baked?

In his in depth review of pie apples, Kenji Alt points out:

Well, there's another thing that acid does: it strengthens pectin, the cement-like glue that holds together the cells of fruit. So looking at this arranged spectrum of apples is actually a pretty good indication of how well each fruit is going to hold up during baking. The further right along the browning scale, the firmer the apple should be in the finished pie.

This same affect will apply to baking apples filled with cranberries: you want an acidic apple, as they are going to hold their shape best when baked.

While I don't know the varieties available to you, he points out that the more acid the apple, the more slowly it browns when cut:

[A]cid can inhibit the browning oxidation reactions that take place in fruit flesh when it is exposed to the air. For this same reason, cooks will store trimmed artichokes in acidulated water—it prevents browning.

The slowest browning, and most acidic of the US apple varieties he tested was Granny Smith. This Whole Foods recipe for cranberry and almond stuffed apples concurs.

This goal of having a sweeter apple to counter-balance the cranberry filling is at odds with needing a more acidic apple to contrast with the cranberries.

Instead, you may be better served by adding sugar to the cranberry filling. Since both cranberries and apples are assertive flavors, they will stand up very well to a sweet filling.

Time and temperature for apples are pretty flexible. A survey of baked apple recipes shows options from 325 F (160 C) for about 45 minute to an hour to 400 F (205 C) for 15 minutes. The important thing is to take them out when they have become tender when tested by pushing a knife point through the body.

Any crisp eating apple will do the job - Braeburn is a good choice, as it has a similar firmness of flesh as a Granny Smith without the tartness. Having said that, if you do find the apple is too tart, you could always add some brown sugar in with the cranberries to help out.

Bake the apples for 20 minutes at 200°C, though if you happen to have the oven on lower for something else, they'll be fine tucked into a corner for a longer period.

As for colouration, I don't there's a great deal you can do, but considering the sauce is going to be covering the apple anyway, what difference does it make?

Can you get Honeycrisp? They're a fairly recently developed variety first cultivated in the US, but I know they have become somewhat more common in other parts of the world. They're truly outstanding for baking and for out of hand eating. They're nice and big, somehow both tart and extra sweet, and they hold their shape very nicely. Average instructions as to time and temperature should be just fine for Honeycrisp if you're lucky enough to be able to get them.

Here's a taste test from National Public Radio and promoted by Serious Eats. Baked Apple Taste Test Although the big winner of that test was Honeycrisp, other varieties did well too.