i would grab that DM-3 even at that price if you don't already have one or a DM-2 although they'd probably take $140. the past month or so they've been clearing on ebay in the $200+ range from what i've seen.
as for the CE-3, that's too much imo. i find those regularly in the $35-50 range, sometimes complete w/ box & manual.
as a reference, last month a local shop here had in a near mint complete w/ box/manual MIJ CE-3 for $59 and would have taken $45 on it and there's a shop here that has like 5 of em in priced @$40 ea. and they would probably go $30-35 on the ones that have been there longer than 3 months.
as for the DM-3, i got mine for a mint complete DD-3 + $80 and felt like i got a deal :)
a few others have popped up locally for $225+ in the past few weeks.