With that budget I would get a new A1200, they are around $200 shipped. I would go the Amikit route unless you want to butt heads with stubborn germans at Vesalia. lol (They canceled my order because I asked a question on here about them! And I was being nice too!)
Then get a nice Commodore RGB monitor and you will be set! You can easily expand the A1200 with a large HD, get a cheap accelerator card, and do all kinds of things like play vintage games or even go online!
In my A1200 I have:
Apollo 1240 68040 @ 33MHz card with 32MB Fast
IBM Travelstar 8GB Notebook HD
PCMCIA Network card
AmigaOS 3.9 Boing Bag 2
