Your dealer .... is there any specific accessories you are looking for? Are you looking for OEM or aftermarket accessories?
I don't think there is a specific on-line supplier in Indiana, they tend to hide their locations although they are all related to authorized dealers. Of course you could contact one of our favourite Supporting Vendors, Jackie at Annapolis Subaru.
Check out her many threads in the Supporting Vendor section and responses by the members who are pleased with her prompt responses, great pricing and very reasonable shipping (which often kills the savings at many online places). They do not have a website, but Jackie can get you practically anything if it is still available. Make sure you tell her you're member here to get her best pricing (and she drives a Forester too :rock.
And if it is OEM supply you are after, no harm in asking your dealers parts-people if they will match pricing, never hurts to ask.