Best way to obtain as many pokemon as possible in gen 3?

I am currently in the process of transferring pokemon from my gen 3 games (I have one of each of them) to my gen 4 games. I want each of them to have a held item that's cool to transfer to gen 4 (type boosters, berries, etc) but I'm running out of boxed pokemon in a few games, namely Emerald and FireRed. What's the cheapest, fastest, and easiest way to just obtain mass numbers of pokemon to transfer to gen 4? I've considered breeding but eggs take forever, especially in FR; and I've considered the Safari Zone, but the Safari Zone lets you capture 30 pokemon per visit, max, and that's only if you don't waste any safari balls. Are there any better ways, besides just catching random wild pokemon?

Bummer part. Items don't transfer. Directly, X/Y.

Easiest is to play thru the game and catch everything you meet. Evolve everything. If you already played thru, go back and walk around and catch pokemon.