Bill,
I just bought a Kenwood KDC-MP632U stereo for my MG Midget. Plays CDs, CD-R, CD-RW, AAC, WMA, MP3 formats, USB Connnection, Aux Input, CD Changer hookup, Remote, all for $145.00. Fits pretty nicely without any real mods to the car. Not sure about the 250's, but I'd think any single DIN stereo would be about the same size wise. I do know that Eclipse makes a nice stereo that is about 3/4" shorter (front to back) than most stereos are.
Just my 2 cents, but I'd stick with Kenwood, Clarion, Pioneer, Alpine or Eclipse. You get what you pay for.
I bought mine online through MillionBuy.Com. They also sell on E-Bay and sometimes you can get a little better price through them going that route.
Hope this helps!