One of the posters down in Dell forums mentioned this a few months ago, when I got my 9300 and was looking for a portable mouse. Went out and tried it the night I read the post and been using it since.
The reciever costs about $18 (with shipping) from Logitech. If you have a MediaPlay mouse and call Logitech customer support you can ask them for a replacement reciever (just tell that the connector is coming loose or something). They'll ask for the s/n from your MediaPlay mouse and will usually send out a new reciever with no problems. If you ask for the reciever and Logitech what you're planning on using it for, they'll give you some hassle. Also, if you ask if any of the mini-reciever dongles work with the MX1000, they'll tell you that the MX1000 works on entirely different technology

You also don't need to use the SetPoint software, unless you need to use something in the software specifically. I've never used Logitech's drivers until recently with my MX518. For the MX1000 / mini-reciever to work all you need do is plug in the reciever, press the little connect button on it, press the connect on the MX1000 and you should be good to go.
Considering the price for the MediaPlay mouse, it is worth just buying the mouse instead of the seperate reciever from Logitech. I haven't tested it with some of the newer, smaller recievers yet.