If anyone can run one of these down I would be very interested, thanks in advance. Apparently they are like unicorns

Did you go on Mercury's website.  Go to its parts section, input your engine's serial number and find the part number of the assembly.  Do a google search for that part number.

There are companies around that change out lower units to convert engines to jet drives and they sell the lower units they remove. Google "outboard to prop conversion". You may get lucky and find somebody there who can help.

58 minutes ago, fishnkamp said:

Did you go on Mercury's website.  Go to its parts section, input your engine's serial number and find the part number of the assembly.  Do a google search for that part number.

Well a new one costs about what the entire engine is worth. Or do you mean search for a used one by part number?

Both, You asked how to find one.

Give these guys a call          http://www.marinepartsoutlet.com/lower_unit.htm

 

Did you destroy your housing or did you have a gear problem.  Many times local shops can fix yours. I had one replaced once due to a major impact and a resulting cracked case. That was on a Merc 200 HP outboard and my insurance paid around $3000. Your 4 stroke 50 should not be that much. 

16 hours ago, fishnkamp said:

Both, You asked how to find one.

Give these guys a call          http://www.marinepartsoutlet.com/lower_unit.htm

 

Did you destroy your housing or did you have a gear problem.  Many times local shops can fix yours. I had one replaced once due to a major impact and a resulting cracked case. That was on a Merc 200 HP outboard and my insurance paid around $3000. Your 4 stroke 50 should not be that much. 

Gotcha thanks. Yes I busted the case, made it back 6-8 Miles to the launch without even noticing 

Well the mechanic has found me a lower unit! fingers crossed...........

 I’m back up and running! I figured out that almost all the engines manufactured like mine are the big foot version. Mine is not the big foot, which is why I always have such a hard time finding parts