Expect to pay for a good strobe. It will likely be as much or more than your compact and housing

BUT a good strobe will last for years and years and will move from one system to the next so you should only have to buy it once. Some strobe options are listed in the pink link - Ike, Sea & Sea and Inon are the three biggies.
There are less expensive options out there.
All photography is light.
Make good decisions now.
The Ikelite housing is great, but may in fact be more than you need if you are not going to add lenses in the future and if you are only using the rig a few times per year. The Canon housings are great but some (the one you are looking at) have oval ports and this means no adding wet mate lenses.