Petsmart will match any price that you bring in to them either printed from the net or from a catalog. I use this all the time to buy whatever I need that they might have in stock at a Petsmart but which would come cheaper from Big Al's. No waiting and no shipping costs. It's the best.
Now as for a filter on a 29 gal, Fluval 204 sounds great. A Rena Filstar XP1 or XP2 would work well. As would a Penguin 200. Or you could do both canister and hang on back, which is what I would recommend most. If you do this you might choose smaller filters, say a Fluval 104 and a Penguin 150. But you get the advantage not only of more efficient cleaning due to their being more filtration surface area, you also get a backup in case one fails as well as the ability to maintenance the filters on a rotating schedule, so you never have to worry about decimating your biofilter by accident. You would also save money on media in the long run because you'll change it a lot less often.
I run a Penguin 125 and a Fluval 104 on my 20g planted blackwater tank, and man is that a sweet system. I hardly ever have to open the Fluval; it's more of my peat treatment / phosphate absorption system and sponge filter than anything else. The Penguin is a workhorse mechanical / biological system. I change the Penguin pad less than once a month and I have never changed anything in the Fluval except for peat and phos-zorb in the eight months its been running. Tank is as perfect as one can imagine.