If you already have a turntable many stereo technicians can switch it over so that the speed and volts are the same. Tape decks also come in switchable models. Most decks run on 15-25 watts. For example if your wattage input is 80, then use a 100 watt transformer. Do NOT use one of the small Franzus converters or you may destroy your machine.
Speakers are of course no problem.
For some strange reason customs will allow you to bring in a receiver, a tapedeck and either a CD or a turntable. Remember to show your receipt. By the way if you want to bring in 2 sets of speakers, then you have to list your stereo as a Quad set. Although I can't guarantee it. Customs is for the most part reasonable if you can show that your receiver has outputs for 2 sets of speakers.