I just checked the old invoices for s***s & giggles. No notation of the gasket brand either time. When it was done the last time in 2012 I know that mechanic just bought everything from the NAPA next door, so I'd guess something they sold. The first time in 2006 really no idea. Nothing about the bolts from the 2006 job either, but on the 2012 job there is a labor charge for the head bolts, so I'd assume that was cleaning them.
Ah I hate to say it, but those dates might be the most telling thing and give you hope if you want to keep that engine. I assumed they were done more recently. Napa, and they got it locally - probably means Fel Pro.
Modern Fel pro gaskets are reasonable choices for EJ25's.
But that wasn't the case back then. Older Fel Pro's, and certainly any other aftermarket gasket they would have chosen back then, were much different and avoided for a long time on EJ25's in the Subaru community. The 2006 was certainly older style and not the newer redesigned Fel Pro's. Your 2012 probably was as well, but I'm not sure. You might be able to google when the newest MLS redesign came out by Fel-Pro.
So - based on the dates, there's probably a good chance that motor is good and not as scary as I thought. But we are still looking at 3 failed gaskets. I'd still go EJ22, though I almost always would. But I'm less inclined to feel twitchy about your engine now.
Cool, I'll see about getting like a core fee from the shop, or selling it myself, if the EJ25 is sell-able.
Engine and trans cores are going the way of the dinosaurs. I haven't given an engine/trans core in...ummm... it was 15 years ago if I did.
If you go get the engine yourself - you pay and they put it in your trunk.
If it's a shop - they don't need to turn it into the yard for a core so just ask for it back.
For $100 someone will probably be ecstatic to use the heads, intake, or cheap rebuild for a toy. But $100 may not be worth the time.