Unless the forester is lifted, a regular scissor jack will be fine.
If you really want a hydraulic jack, I use the Pro-Lift B-006D on my 4runner with big tyres, so if it can work there it can probably work for you! Probably don't need a 6 ton model for yourself, so if the 4 ton is cheaper can always go with that.
It is quick and easy to lift once you set it in the right spot.
What are your requirements for the Hydraulic Jack? Lifting height? Weight of the jack itself? Cargo space? Better question, how often have you actually needed to fix/replace a flat tire? With my 3 vehicles (2001 Forester, 2014 Mercedes and 2013 Nissan Leaf), from 2001 until today, I have only had 2 occasions where I have needed road side tire replacement. Once on the 2001 Forester and shredded the tire and used the onboard scissor jack just fine. 2nd time with 2013 VW Jetta TDI, TPMS kicked light and noticed it was a slow leak and I refilled and drove the rest of the way home.
All other occasions where I have had tire leaks were at home when I inspected the tires during tire rotation and found and noticed metal objects in the tire and immediately patch the respective holes.
My point being you're going to spend some money on something that you will likely never use and adds extra weight to your vehicle and take up extra space. Just my 2cents worth.
What is wrong with the oem jack? If it is missing you can buy one off the dealer. Or my favorite Ebay. Heck even cheaper, any junk yard.
But...if you really want a compact hydraulic jack, you can't go wrong with Harbor Fright Pittsburg aluminum racing jack for like $80. Sometimes they go on sale for like $70.
AutoX guys love this little guy. It's light, quick and compact. That's my recommendation.
Floor jacks can get heavy quick. The alloy jacks are much easier to handle, might be worth considering a sill adaptor too so you don't end up bending anything
A bottle jack might be a good alternative idea but perhaps less stable vs a floor jack?
The factory scissor jack really is not ideal on anything but perfectly level and firm ground. If the vehicle is parked at any kind of angle or partway up a curb, you risk bending a scissor jack.
If you don't care about the weight, Costco used to do a great jack that is built like a tank.
Edit: In addition to a jack, it might be worth considering the below examples of items in addition to some gloves too: 1/2 in. Drive 25 in. Breaker Bar (If you have room in the back to stash that somewhere)