Hey John, welcome to Club Cobra!
Beautiful Shell Valley. I like how the paint goes thru the dash, that's neat. Looks to be in a great condition.
As far as parts. It is not as hard as it sounds. Filter wise, depends what your car is set up for but just take the old one off and see what size it is, and get something similar in size. For the
oil, depends on the pan you have and if you are running an
oil cooler for example (can't tell from the pic). But they usually are in the 8 to 10 qts range. Brake pads, I don't know enough about the Valleys to help you out. A lot of these cars use fairly common parts. Don't be afraid to ask (and use the search botton

)
Check out the Windy City section too if you haven't already. Peoria heh? Fun stuff down there... I go there for work once in a while, fairly drury doen there, except for the school bus races at the speedway lol. Your Javelin looks great!
Once again welcome, and please don't feed Patrick
Arno