As someone who is seemingly constantly working on computers and has done a ton of engine building and other deep car stuff, in addition to the garage mentioned previously, I'd recommend buying a buildable engine core for your subaru, getting that built (either do it yourself - recommended, or by a machine shop - will probably work well, but will cost a lot of $$) and having it ready to install rather than trying to pull the existing engine out and rebuilding it - especially if the current engine still runs.

Unless your plan is to make a hobby of having exploded cars in the yard, this'll go a long way towards putting an end in sight for an engine rebuilding venture.

Also fuck all car subscriptions - that's some gross profiteering right there...