Find a reputable seller that is trying to sell a used DA50. I see them all the time on R/C Universe for $325 and up.
I see alot of guys are trying upgrade to a DA60 and sell the 50's. Just my two cents of thought.
The DLE55 has a bit more power but service is better with the DA. I've got 2 DA50's and both run solid. As
for the frame check out Aztech R/C he has a Raven available and is a super person to deal with.