$$$ to repair 2010 head gasket

Don't take their fear-mongering too seriously. Almoist everyone resealing Subaru heads now knows to use the newer three-ply HGs. (It's not about original vs steel...they're BOTH steel.) Half-shafts (cv axles) are available online for a song. Only a smallish (but significant) percentage of them are sufficiently unsmooth enough to shake or rattle at speed. Worst case you eat the second one-hour labor charge, so don't sweat it. However, I WOULD use a shop experienced with Subie HG jobs, AND will send your heads out for measuring and pressure-testing at a reputable machine shop. You do NOT want to reinstall a warped nor cracked head and have to repeat a 10 hr job. This is a perfect time to replace the removed t-belt and inspect its pulleys too; however the water pumps are golden, so don't go overboard. Ask your wrench if he has experience carefully torquing the heads, as that's important too. This is about a $1300 wholesale job in New England, growing to $1500-1700 retail. Add the axle in for only $200 total. Given that you like your Forester (not my taste), a 2010 isn't so old as to not spend up to $2k on it, unless perhaps you need all brakes, tires, and maybe a cat conv at the same time, as $3.5 to $4k total would give me pause. OTOH if the oil leak is minor, and only on the left (passenger side), you MAY be able to stave off HG replacement quite awhile by increasing oil viscosity to 10w30-40...or preferably even 15w40.... You may see the leak diminish sufficiently to not coat and odoriferously cook off the cat-pipe beneath it. That said, keep an eye on coolant level, as you may also be leaking coolant from the DRIVER's side rear (#4) cylinder corner. Once both sides are leaking you should bite the bullet. (This dual- leak both-sides scenario is sufficient reason to NEVER just replace one side head gasket for a discount (usually 2/3 the labor cost), as the opposite side is needed eventually...and indeed soon after!

Edit: close parenthesis

Use a top quality multi layer head gasket such as 5 star. The factory head gaskets are a major reason why they fail. If the oil leak is small I would live with it.

Buy a Toyota. Any Toyota.

In other words give up driving enjoyment?

I'm surprised you managed to get 180k miles on it. I started having this issue at about 90k miles on it. It started with rough idling. I am still debating if I should sell my Subi and get a newer forester say 2014 and newer because I believe Subaru fixed the issue (correct me if I'm wrong).

You'll be disappointed with the Forester's handling. Subaru started using the better HG on the old SPHC 2.5i in 2010. The newer, better 2.5 DOHC has no HG issues.

I have a 2014 forester under 67Km. Head gasket was found leaking recently when I went to dealership for maintenance. Considering to sell it as I no longer trust Subaru. Dealer quoted $3000on this.

I have a 2010 Forester at 128,000 KM and the head gasket is leaking. Ridiculous that the head gasket is going already! Should last twice as long as this....I thought Subaru's were good cars? Is it worth spending 3K to replace this and the timing belt?

No, but it's worth $1.6k to do it, including outside machine shop vetting of the integrity of the heads. The OE gaskets probably aged out (11 winters), rather than mileage correlated.