All the "traditional" housings in that price range, Ikelite, Equinox, Amphibico, TopDawg etc. are pretty heavy - and bulky. Most in the 8-12 lb. range since they partially compensate for the volume of air trapped inside the housing with increased weight.
A good option might be one of the Canon models in their proprietary WP-V4 housing -
Canon U.S.A. : Consumer : WP-V4 Waterproof Case
B&H has it for $479 currently:
Canon WP-V4 Waterproof Case 6122B002 B&H Photo Video It's also 2.7lbs.
The cameras that fit it are the:
Vixia HF MF500 ($539)
Vixia HF MF50 ($649)
Vixia HF MF52 ($749).
Note that
only these 3 models work in the housing. The chief differences afaik are the amount of onboard vs. removable flash memory and the 2 better models have built-in WiFi. All three have both optical and electronic image stabilization for the wakeboarding. They're all pretty small also.
The housing has some limitations - 130' depth rating and more limited controls. It does have all the needed stuff, on/off, zoom/tele, photo/video, but when the camera is in the case you can only see but not access the LCD touch screen. It is however lightweight and since it's molded around those specific cameras - pretty compact. Obviously a good solution for wakeboarding also.
My buddy shoots a previous model, I've seen the video, he gets excellent results. The camera also has an u/w mode pre-set but you have to set it before the camera is sealed in the housing - the results were a little weak though. Since the housing does have a threaded glass port, you can also buy a standard color correcting red filter that can be removed u/w when needed. They're about $60. If your sister is mostly shooting above 60' or so in bright water, you don't need lights, just the filter. Below that or in darker areas - or for macro work - she might want light(s).
One light option is the L&M Sola 1200
Video light, it's a lot of light for $699. Their $89 tray option should work with the Canon housing as it has a standard tripod mount but verify that with Bluewater.
Light & Motion Sola 1200 Video Light | Bluewater Photo & Video It's a very small light also.
Optimally you want two for coverage but that pushes your budget. And one will work for macro etc - she'll just have to position it and watch the shadows. The Sola has a flood beam option which helps.
If you can squeeze $200 more out of the budget, there's also the Sola 2000 - same basic light just more output. There are also less expensive options - I'm somewhat partial to L&M as they have a good reputation. Another option might be:
I-Torch Video Pro4 Light | Bluewater Photo & Video at $499 - IDK much about them. Optical Ocean Sales also has some other affordable options - note that anything that says focus/modeling light
is not bright enough for video.
Focus & Video Lights - Optical Ocean Sales Underwater Photo - 800-359-1295!
Since the safari videos will be shot at distance, maybe get a $25+ Monopod for stability. They're collapsible and travel well. I'm a big fan of optical zoom - the Canon's are 10X - for longer range shots vs. electronic zoom.
