^^^^^well, that still depends on what you're planning to do. The mpc can easily be replaced by those emulator x cards assuming you have a pc which is fairly up to date ( though still very complex, you'll be thrown into the deep abyss of signal routing but a good way to learn basics ), add a korg microkontrol midicontroller ( with 16 drumpads you can assign to the EMUx samplersoftware ) and you're rocking a 24bit/96kHz sampler/workstation compared to the 16bit/44kHz mpc1k/2k/2kxl. It'll get you a bit further anyway, not saying you shouldn't buy the mpc1k, but consider it a luxury item on a $1000 budget.
Handytrax, oke, it's funny and portable but what you need is pick-up with a good needle, who cares what brand, it's for sampling purpose so a $5 Dual occasion with a new needle makes the same result.
That's 300 for the EmulatorX, 350 on the microkontrol and (oke 5 is a bit on the low ) 30 buck for a cheapo pickup and 20 bucks for a new needle.
You'd be left with 500 bucks that you can spend on good monitors as they're the most important item in your little studio.
Another thing is to keep in mind that a lot of hardware needs at least a good 16chnl mixer ( no , behringer is not an option ), you can expect to pay at least 500 to 600 for one. You wont need a mixer in this setup, but if you intend to upgrade to synths etc you can always expand to the EMU breakout box which offers preamp for mic and 8 analog in and out ( and digital ).
Keep in mind that buying one item for your setup could mean adapting your current setup, or in your case, buy gear that can easily integrate together and efficiently.
And again, scope out through the forum, you're not the first.