Volvo Repair: ECU replacement 1993 240, junk yard, exact number

Question
I am the proud owner of a 1993 240 "classic" (#1312/1600).
My ECU needs to be replaced.
what exact number/code should I be looking for in replacing this?
A good mechanic in my town says that I should only replace this with OEM or Bosch.
What do you recommend? can I go to a junk yard or Ebay and find a used one? If so, are there other model #'s from older 240's that would work as well?
I just dont want to spend the $1000.00 for a new one if i can help it.
thank you so much.
raymond

Answer
Raymond, stick with Bosch.  the number should be a 561 ECU but remove the panel and look to see whats on yours just to be sure.  Junkyard boxes are great for short term but you dont know what you are getting with those.  A buddy of mine on EBay has great 240 stuff.  Check him out.  His ID is 240salvage.  Roger