It won't be as closed as the PS3 seems to be. IIRC Vita's devkits are the cheapest PlayStation devkits at launch in the history of the brand. Looking around, it seems that Europeans will pay 1900 (or like $2600 straight conversion). As for how an indie can get it, well it seems pretty easily. A bunch of small indie studios are making Vita games. I don't know exactly how and where to get a devkit, but I imagine snooping around Sony's
Developer Website might result in something. As for development assistance, Sony is known for being very helpful, but I wouldn't know.
I only suggest Suite since if I were an indie studio I'd be much more interested in targeting Vita, Android, and potentially more than just Vita with one release. There's also supposed to be some developer's community for Suite.