My suggestion: Forget it.
Longer version: I don't know anyone who has any in stock,
and the last one I saw on eBay went for £131. Yes, that's
~USD 238, ~EUR 164! Crazy, eh?
Ok. That wasn't a very helpful answer. Where do you live?
If you have PAL, use LCD TV instead. There are also supposed
to be some monitors that can sync down to Amiga modes,
but I haven't tried any. Perhaps someone who has tried
any of these can suggest one?
If you really want to shell out for a ScanDoubler on eBay,
be aware that some of them can't display the full AGA
palette in your A1200, meaning bleaker colours. If this
matters to you, check
Amiga Hardware Database, or
Big Book of Amiga Hardware before placing your bid.
