Most things will be special order, shipped from warehouse; can take anywhere from 2 days to a couple of weeks (usually averages 3-4 business days for common things). The OEM part network is massive and pretty efficient; you'll only run into trouble if there is some kind of shortage or supply chain issue.
I have no specific loyalty. My recommendation is to cross-shop Toyota and Subaru to see who has better prices. Toyota has a slightly better/more available online parts system and local-dealer discounts. Subaru local-dealer discounts often aren't as aggressive percentage wise, but sometimes the base prices are simply better through Subaru (most parts sold by Toyota come from Subaru with a Toyota label slapped over it). It's usually free to order online and pick-up in person, with paid shipping to your door as an option.
You can even try online Subaru/Toyota parts stores "subaru online parts, toyota parts warehouse, other generic name": they are usually just dealerships operating an online parts distribution business on the side. Prices are often lower, but you have to pay for shipping and returns are harder. However, if you have a large order of items you can usually save a dollar even with ship costs.
https://parts.subaru.com/
https://parts.toyota.com/