What size catch can?

With all the auto parts places in Philly, just go to Pep's or any of the others and get whatever they have... About $7 will get you a 1.5quart, $10 will get you a 2.5quart. I just put the smaller one on my 318 car because the other universal type bottle someone else put on years ago cracked.
Not exactly something that needs to be extravagant, save your money for the places you actually need to spend it...
Hell, you could zip tie a 2litre soda bottle in the if you're a real cheap b*stard
(just run the hose all the way down into the bottle).